LCOV - code coverage report
Current view: top level - fs - binfmt_elf.c (source / functions) Hit Total Coverage
Test: landlock.info Lines: 406 497 81.7 %
Date: 2021-04-22 12:43:58 Functions: 12 14 85.7 %

          Line data    Source code
       1             : // SPDX-License-Identifier: GPL-2.0-only
       2             : /*
       3             :  * linux/fs/binfmt_elf.c
       4             :  *
       5             :  * These are the functions used to load ELF format executables as used
       6             :  * on SVr4 machines.  Information on the format may be found in the book
       7             :  * "UNIX SYSTEM V RELEASE 4 Programmers Guide: Ansi C and Programming Support
       8             :  * Tools".
       9             :  *
      10             :  * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
      11             :  */
      12             : 
      13             : #include <linux/module.h>
      14             : #include <linux/kernel.h>
      15             : #include <linux/fs.h>
      16             : #include <linux/log2.h>
      17             : #include <linux/mm.h>
      18             : #include <linux/mman.h>
      19             : #include <linux/errno.h>
      20             : #include <linux/signal.h>
      21             : #include <linux/binfmts.h>
      22             : #include <linux/string.h>
      23             : #include <linux/file.h>
      24             : #include <linux/slab.h>
      25             : #include <linux/personality.h>
      26             : #include <linux/elfcore.h>
      27             : #include <linux/init.h>
      28             : #include <linux/highuid.h>
      29             : #include <linux/compiler.h>
      30             : #include <linux/highmem.h>
      31             : #include <linux/hugetlb.h>
      32             : #include <linux/pagemap.h>
      33             : #include <linux/vmalloc.h>
      34             : #include <linux/security.h>
      35             : #include <linux/random.h>
      36             : #include <linux/elf.h>
      37             : #include <linux/elf-randomize.h>
      38             : #include <linux/utsname.h>
      39             : #include <linux/coredump.h>
      40             : #include <linux/sched.h>
      41             : #include <linux/sched/coredump.h>
      42             : #include <linux/sched/task_stack.h>
      43             : #include <linux/sched/cputime.h>
      44             : #include <linux/sizes.h>
      45             : #include <linux/types.h>
      46             : #include <linux/cred.h>
      47             : #include <linux/dax.h>
      48             : #include <linux/uaccess.h>
      49             : #include <asm/param.h>
      50             : #include <asm/page.h>
      51             : 
      52             : #ifndef ELF_COMPAT
      53             : #define ELF_COMPAT 0
      54             : #endif
      55             : 
      56             : #ifndef user_long_t
      57             : #define user_long_t long
      58             : #endif
      59             : #ifndef user_siginfo_t
      60             : #define user_siginfo_t siginfo_t
      61             : #endif
      62             : 
      63             : /* That's for binfmt_elf_fdpic to deal with */
      64             : #ifndef elf_check_fdpic
      65             : #define elf_check_fdpic(ex) false
      66             : #endif
      67             : 
      68             : static int load_elf_binary(struct linux_binprm *bprm);
      69             : 
      70             : #ifdef CONFIG_USELIB
      71             : static int load_elf_library(struct file *);
      72             : #else
      73             : #define load_elf_library NULL
      74             : #endif
      75             : 
      76             : /*
      77             :  * If we don't support core dumping, then supply a NULL so we
      78             :  * don't even try.
      79             :  */
      80             : #ifdef CONFIG_ELF_CORE
      81             : static int elf_core_dump(struct coredump_params *cprm);
      82             : #else
      83             : #define elf_core_dump   NULL
      84             : #endif
      85             : 
      86             : #if ELF_EXEC_PAGESIZE > PAGE_SIZE
      87             : #define ELF_MIN_ALIGN   ELF_EXEC_PAGESIZE
      88             : #else
      89             : #define ELF_MIN_ALIGN   PAGE_SIZE
      90             : #endif
      91             : 
      92             : #ifndef ELF_CORE_EFLAGS
      93             : #define ELF_CORE_EFLAGS 0
      94             : #endif
      95             : 
      96             : #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
      97             : #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
      98             : #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
      99             : 
     100             : static struct linux_binfmt elf_format = {
     101             :         .module         = THIS_MODULE,
     102             :         .load_binary    = load_elf_binary,
     103             :         .load_shlib     = load_elf_library,
     104             :         .core_dump      = elf_core_dump,
     105             :         .min_coredump   = ELF_EXEC_PAGESIZE,
     106             : };
     107             : 
     108             : #define BAD_ADDR(x) (unlikely((unsigned long)(x) >= TASK_SIZE))
     109             : 
     110        1129 : static int set_brk(unsigned long start, unsigned long end, int prot)
     111             : {
     112        1129 :         start = ELF_PAGEALIGN(start);
     113        1129 :         end = ELF_PAGEALIGN(end);
     114        1129 :         if (end > start) {
     115             :                 /*
     116             :                  * Map the last of the bss segment.
     117             :                  * If the header is requesting these pages to be
     118             :                  * executable, honour that (ppc32 needs this).
     119             :                  */
     120         496 :                 int error = vm_brk_flags(start, end - start,
     121             :                                 prot & PROT_EXEC ? VM_EXEC : 0);
     122         496 :                 if (error)
     123             :                         return error;
     124             :         }
     125        1129 :         current->mm->start_brk = current->mm->brk = end;
     126        1129 :         return 0;
     127             : }
     128             : 
     129             : /* We need to explicitly zero any fractional pages
     130             :    after the data section (i.e. bss).  This would
     131             :    contain the junk from the file that should not
     132             :    be in memory
     133             :  */
     134        2256 : static int padzero(unsigned long elf_bss)
     135             : {
     136        2256 :         unsigned long nbyte;
     137             : 
     138        2256 :         nbyte = ELF_PAGEOFFSET(elf_bss);
     139        2256 :         if (nbyte) {
     140        2256 :                 nbyte = ELF_MIN_ALIGN - nbyte;
     141        2256 :                 if (clear_user((void __user *) elf_bss, nbyte))
     142           0 :                         return -EFAULT;
     143             :         }
     144             :         return 0;
     145             : }
     146             : 
     147             : /* Let's use some macros to make this stack manipulation a little clearer */
     148             : #ifdef CONFIG_STACK_GROWSUP
     149             : #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) + (items))
     150             : #define STACK_ROUND(sp, items) \
     151             :         ((15 + (unsigned long) ((sp) + (items))) &~ 15UL)
     152             : #define STACK_ALLOC(sp, len) ({ \
     153             :         elf_addr_t __user *old_sp = (elf_addr_t __user *)sp; sp += len; \
     154             :         old_sp; })
     155             : #else
     156             : #define STACK_ADD(sp, items) ((elf_addr_t __user *)(sp) - (items))
     157             : #define STACK_ROUND(sp, items) \
     158             :         (((unsigned long) (sp - items)) &~ 15UL)
     159             : #define STACK_ALLOC(sp, len) ({ sp -= len ; sp; })
     160             : #endif
     161             : 
     162             : #ifndef ELF_BASE_PLATFORM
     163             : /*
     164             :  * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture.
     165             :  * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value
     166             :  * will be copied to the user stack in the same manner as AT_PLATFORM.
     167             :  */
     168             : #define ELF_BASE_PLATFORM NULL
     169             : #endif
     170             : 
     171             : static int
     172        1129 : create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec,
     173             :                 unsigned long load_addr, unsigned long interp_load_addr,
     174             :                 unsigned long e_entry)
     175             : {
     176        1129 :         struct mm_struct *mm = current->mm;
     177        1129 :         unsigned long p = bprm->p;
     178        1129 :         int argc = bprm->argc;
     179        1129 :         int envc = bprm->envc;
     180        1129 :         elf_addr_t __user *sp;
     181        1129 :         elf_addr_t __user *u_platform;
     182        1129 :         elf_addr_t __user *u_base_platform;
     183        1129 :         elf_addr_t __user *u_rand_bytes;
     184        1129 :         const char *k_platform = ELF_PLATFORM;
     185        1129 :         const char *k_base_platform = ELF_BASE_PLATFORM;
     186        1129 :         unsigned char k_rand_bytes[16];
     187        1129 :         int items;
     188        1129 :         elf_addr_t *elf_info;
     189        1129 :         elf_addr_t flags = 0;
     190        1129 :         int ei_index;
     191        1129 :         const struct cred *cred = current_cred();
     192        1129 :         struct vm_area_struct *vma;
     193             : 
     194             :         /*
     195             :          * In some cases (e.g. Hyper-Threading), we want to avoid L1
     196             :          * evictions by the processes running on the same package. One
     197             :          * thing we can do is to shuffle the initial stack for them.
     198             :          */
     199             : 
     200        1129 :         p = arch_align_stack(p);
     201             : 
     202             :         /*
     203             :          * If this architecture has a platform capability string, copy it
     204             :          * to userspace.  In some cases (Sparc), this info is impossible
     205             :          * for userspace to get any other way, in others (i386) it is
     206             :          * merely difficult.
     207             :          */
     208        1129 :         u_platform = NULL;
     209        1129 :         if (k_platform) {
     210        1129 :                 size_t len = strlen(k_platform) + 1;
     211             : 
     212        1129 :                 u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
     213        1129 :                 if (copy_to_user(u_platform, k_platform, len))
     214             :                         return -EFAULT;
     215             :         }
     216             : 
     217             :         /*
     218             :          * If this architecture has a "base" platform capability
     219             :          * string, copy it to userspace.
     220             :          */
     221        1129 :         u_base_platform = NULL;
     222        1129 :         if (k_base_platform) {
     223             :                 size_t len = strlen(k_base_platform) + 1;
     224             : 
     225             :                 u_base_platform = (elf_addr_t __user *)STACK_ALLOC(p, len);
     226             :                 if (copy_to_user(u_base_platform, k_base_platform, len))
     227             :                         return -EFAULT;
     228             :         }
     229             : 
     230             :         /*
     231             :          * Generate 16 random bytes for userspace PRNG seeding.
     232             :          */
     233        1129 :         get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
     234        1129 :         u_rand_bytes = (elf_addr_t __user *)
     235        1129 :                        STACK_ALLOC(p, sizeof(k_rand_bytes));
     236        1129 :         if (copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
     237             :                 return -EFAULT;
     238             : 
     239             :         /* Create the ELF interpreter info */
     240        1129 :         elf_info = (elf_addr_t *)mm->saved_auxv;
     241             :         /* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
     242             : #define NEW_AUX_ENT(id, val) \
     243             :         do { \
     244             :                 *elf_info++ = id; \
     245             :                 *elf_info++ = val; \
     246             :         } while (0)
     247             : 
     248             : #ifdef ARCH_DLINFO
     249             :         /* 
     250             :          * ARCH_DLINFO must come first so PPC can do its special alignment of
     251             :          * AUXV.
     252             :          * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
     253             :          * ARCH_DLINFO changes
     254             :          */
     255        1129 :         ARCH_DLINFO;
     256             : #endif
     257        1129 :         NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
     258        1129 :         NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
     259        1129 :         NEW_AUX_ENT(AT_CLKTCK, CLOCKS_PER_SEC);
     260        1129 :         NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff);
     261        1129 :         NEW_AUX_ENT(AT_PHENT, sizeof(struct elf_phdr));
     262        1129 :         NEW_AUX_ENT(AT_PHNUM, exec->e_phnum);
     263        1129 :         NEW_AUX_ENT(AT_BASE, interp_load_addr);
     264        1129 :         if (bprm->interp_flags & BINPRM_FLAGS_PRESERVE_ARGV0)
     265           0 :                 flags |= AT_FLAGS_PRESERVE_ARGV0;
     266        1129 :         NEW_AUX_ENT(AT_FLAGS, flags);
     267        1129 :         NEW_AUX_ENT(AT_ENTRY, e_entry);
     268        1129 :         NEW_AUX_ENT(AT_UID, from_kuid_munged(cred->user_ns, cred->uid));
     269        1129 :         NEW_AUX_ENT(AT_EUID, from_kuid_munged(cred->user_ns, cred->euid));
     270        1129 :         NEW_AUX_ENT(AT_GID, from_kgid_munged(cred->user_ns, cred->gid));
     271        1129 :         NEW_AUX_ENT(AT_EGID, from_kgid_munged(cred->user_ns, cred->egid));
     272        1129 :         NEW_AUX_ENT(AT_SECURE, bprm->secureexec);
     273        1129 :         NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
     274             : #ifdef ELF_HWCAP2
     275        1129 :         NEW_AUX_ENT(AT_HWCAP2, ELF_HWCAP2);
     276             : #endif
     277        1129 :         NEW_AUX_ENT(AT_EXECFN, bprm->exec);
     278        1129 :         if (k_platform) {
     279        1129 :                 NEW_AUX_ENT(AT_PLATFORM,
     280             :                             (elf_addr_t)(unsigned long)u_platform);
     281             :         }
     282        1129 :         if (k_base_platform) {
     283        1129 :                 NEW_AUX_ENT(AT_BASE_PLATFORM,
     284             :                             (elf_addr_t)(unsigned long)u_base_platform);
     285             :         }
     286        1129 :         if (bprm->have_execfd) {
     287           0 :                 NEW_AUX_ENT(AT_EXECFD, bprm->execfd);
     288             :         }
     289             : #undef NEW_AUX_ENT
     290             :         /* AT_NULL is zero; clear the rest too */
     291        1129 :         memset(elf_info, 0, (char *)mm->saved_auxv +
     292        1129 :                         sizeof(mm->saved_auxv) - (char *)elf_info);
     293             : 
     294             :         /* And advance past the AT_NULL entry.  */
     295        1129 :         elf_info += 2;
     296             : 
     297        1129 :         ei_index = elf_info - (elf_addr_t *)mm->saved_auxv;
     298        1129 :         sp = STACK_ADD(p, ei_index);
     299             : 
     300        1129 :         items = (argc + 1) + (envc + 1) + 1;
     301        1129 :         bprm->p = STACK_ROUND(sp, items);
     302             : 
     303             :         /* Point sp at the lowest address on the stack */
     304             : #ifdef CONFIG_STACK_GROWSUP
     305             :         sp = (elf_addr_t __user *)bprm->p - items - ei_index;
     306             :         bprm->exec = (unsigned long)sp; /* XXX: PARISC HACK */
     307             : #else
     308        1129 :         sp = (elf_addr_t __user *)bprm->p;
     309             : #endif
     310             : 
     311             : 
     312             :         /*
     313             :          * Grow the stack manually; some architectures have a limit on how
     314             :          * far ahead a user-space access may be in order to grow the stack.
     315             :          */
     316        1129 :         if (mmap_read_lock_killable(mm))
     317             :                 return -EINTR;
     318        1129 :         vma = find_extend_vma(mm, bprm->p);
     319        1129 :         mmap_read_unlock(mm);
     320        1129 :         if (!vma)
     321             :                 return -EFAULT;
     322             : 
     323             :         /* Now, let's put argc (and argv, envp if appropriate) on the stack */
     324        1129 :         if (put_user(argc, sp++))
     325             :                 return -EFAULT;
     326             : 
     327             :         /* Populate list of argv pointers back to argv strings. */
     328        1129 :         p = mm->arg_end = mm->arg_start;
     329        4210 :         while (argc-- > 0) {
     330        3081 :                 size_t len;
     331        3081 :                 if (put_user((elf_addr_t)p, sp++))
     332             :                         return -EFAULT;
     333        3081 :                 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
     334        3081 :                 if (!len || len > MAX_ARG_STRLEN)
     335             :                         return -EINVAL;
     336        3081 :                 p += len;
     337             :         }
     338        1129 :         if (put_user(0, sp++))
     339             :                 return -EFAULT;
     340        1129 :         mm->arg_end = p;
     341             : 
     342             :         /* Populate list of envp pointers back to envp strings. */
     343        1129 :         mm->env_end = mm->env_start = p;
     344       18273 :         while (envc-- > 0) {
     345       17144 :                 size_t len;
     346       17144 :                 if (put_user((elf_addr_t)p, sp++))
     347             :                         return -EFAULT;
     348       17144 :                 len = strnlen_user((void __user *)p, MAX_ARG_STRLEN);
     349       17144 :                 if (!len || len > MAX_ARG_STRLEN)
     350             :                         return -EINVAL;
     351       17144 :                 p += len;
     352             :         }
     353        1129 :         if (put_user(0, sp++))
     354             :                 return -EFAULT;
     355        1129 :         mm->env_end = p;
     356             : 
     357             :         /* Put the elf_info on the stack in the right place.  */
     358        2258 :         if (copy_to_user(sp, mm->saved_auxv, ei_index * sizeof(elf_addr_t)))
     359           0 :                 return -EFAULT;
     360             :         return 0;
     361             : }
     362             : 
     363        9022 : static unsigned long elf_map(struct file *filep, unsigned long addr,
     364             :                 const struct elf_phdr *eppnt, int prot, int type,
     365             :                 unsigned long total_size)
     366             : {
     367        9022 :         unsigned long map_addr;
     368        9022 :         unsigned long size = eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr);
     369        9022 :         unsigned long off = eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr);
     370        9022 :         addr = ELF_PAGESTART(addr);
     371        9022 :         size = ELF_PAGEALIGN(size);
     372             : 
     373             :         /* mmap() will return -EINVAL if given a zero size, but a
     374             :          * segment with zero filesize is perfectly valid */
     375        9022 :         if (!size)
     376             :                 return addr;
     377             : 
     378             :         /*
     379             :         * total_size is the size of the ELF (interpreter) image.
     380             :         * The _first_ mmap needs to know the full size, otherwise
     381             :         * randomization might put this image into an overlapping
     382             :         * position with the ELF binary image. (since size < total_size)
     383             :         * So we first map the 'big' image - and unmap the remainder at
     384             :         * the end. (which unmap is needed for ELF images with holes.)
     385             :         */
     386        9022 :         if (total_size) {
     387        2254 :                 total_size = ELF_PAGEALIGN(total_size);
     388        2254 :                 map_addr = vm_mmap(filep, addr, total_size, prot, type, off);
     389        2254 :                 if (!BAD_ADDR(map_addr))
     390        2254 :                         vm_munmap(map_addr+size, total_size-size);
     391             :         } else
     392        6768 :                 map_addr = vm_mmap(filep, addr, size, prot, type, off);
     393             : 
     394        9022 :         if ((type & MAP_FIXED_NOREPLACE) &&
     395        3381 :             PTR_ERR((void *)map_addr) == -EEXIST)
     396           0 :                 pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n",
     397             :                         task_pid_nr(current), current->comm, (void *)addr);
     398             : 
     399             :         return(map_addr);
     400             : }
     401             : 
     402        2254 : static unsigned long total_mapping_size(const struct elf_phdr *cmds, int nr)
     403             : {
     404        2254 :         int i, first_idx = -1, last_idx = -1;
     405             : 
     406       24809 :         for (i = 0; i < nr; i++) {
     407       22555 :                 if (cmds[i].p_type == PT_LOAD) {
     408        9014 :                         last_idx = i;
     409        9014 :                         if (first_idx == -1)
     410        2254 :                                 first_idx = i;
     411             :                 }
     412             :         }
     413        2254 :         if (first_idx == -1)
     414             :                 return 0;
     415             : 
     416        2254 :         return cmds[last_idx].p_vaddr + cmds[last_idx].p_memsz -
     417        2254 :                                 ELF_PAGESTART(cmds[first_idx].p_vaddr);
     418             : }
     419             : 
     420        4510 : static int elf_read(struct file *file, void *buf, size_t len, loff_t pos)
     421             : {
     422        4510 :         ssize_t rv;
     423             : 
     424        4510 :         rv = kernel_read(file, buf, len, &pos);
     425        4510 :         if (unlikely(rv != len)) {
     426           0 :                 return (rv < 0) ? rv : -EIO;
     427             :         }
     428             :         return 0;
     429             : }
     430             : 
     431        1127 : static unsigned long maximum_alignment(struct elf_phdr *cmds, int nr)
     432             : {
     433        1127 :         unsigned long alignment = 0;
     434        1127 :         int i;
     435             : 
     436       13539 :         for (i = 0; i < nr; i++) {
     437       12412 :                 if (cmds[i].p_type == PT_LOAD) {
     438        4506 :                         unsigned long p_align = cmds[i].p_align;
     439             : 
     440             :                         /* skip non-power of two alignments as invalid */
     441        9012 :                         if (!is_power_of_2(p_align))
     442           0 :                                 continue;
     443        4506 :                         alignment = max(alignment, p_align);
     444             :                 }
     445             :         }
     446             : 
     447             :         /* ensure we align to at least one page */
     448        1127 :         return ELF_PAGEALIGN(alignment);
     449             : }
     450             : 
     451             : /**
     452             :  * load_elf_phdrs() - load ELF program headers
     453             :  * @elf_ex:   ELF header of the binary whose program headers should be loaded
     454             :  * @elf_file: the opened ELF binary file
     455             :  *
     456             :  * Loads ELF program headers from the binary file elf_file, which has the ELF
     457             :  * header pointed to by elf_ex, into a newly allocated array. The caller is
     458             :  * responsible for freeing the allocated data. Returns an ERR_PTR upon failure.
     459             :  */
     460        2256 : static struct elf_phdr *load_elf_phdrs(const struct elfhdr *elf_ex,
     461             :                                        struct file *elf_file)
     462             : {
     463        2256 :         struct elf_phdr *elf_phdata = NULL;
     464        2256 :         int retval, err = -1;
     465        2256 :         unsigned int size;
     466             : 
     467             :         /*
     468             :          * If the size of this structure has changed, then punt, since
     469             :          * we will be doing the wrong thing.
     470             :          */
     471        2256 :         if (elf_ex->e_phentsize != sizeof(struct elf_phdr))
     472           0 :                 goto out;
     473             : 
     474             :         /* Sanity check the number of program headers... */
     475             :         /* ...and their total size. */
     476        2256 :         size = sizeof(struct elf_phdr) * elf_ex->e_phnum;
     477        2256 :         if (size == 0 || size > 65536 || size > ELF_MIN_ALIGN)
     478           0 :                 goto out;
     479             : 
     480        2256 :         elf_phdata = kmalloc(size, GFP_KERNEL);
     481        2256 :         if (!elf_phdata)
     482           0 :                 goto out;
     483             : 
     484             :         /* Read in the program headers */
     485        2256 :         retval = elf_read(elf_file, elf_phdata, size, elf_ex->e_phoff);
     486        2256 :         if (retval < 0) {
     487           0 :                 err = retval;
     488           0 :                 goto out;
     489             :         }
     490             : 
     491             :         /* Success! */
     492             :         err = 0;
     493           0 : out:
     494           0 :         if (err) {
     495           0 :                 kfree(elf_phdata);
     496           0 :                 elf_phdata = NULL;
     497             :         }
     498        2256 :         return elf_phdata;
     499             : }
     500             : 
     501             : #ifndef CONFIG_ARCH_BINFMT_ELF_STATE
     502             : 
     503             : /**
     504             :  * struct arch_elf_state - arch-specific ELF loading state
     505             :  *
     506             :  * This structure is used to preserve architecture specific data during
     507             :  * the loading of an ELF file, throughout the checking of architecture
     508             :  * specific ELF headers & through to the point where the ELF load is
     509             :  * known to be proceeding (ie. SET_PERSONALITY).
     510             :  *
     511             :  * This implementation is a dummy for architectures which require no
     512             :  * specific state.
     513             :  */
     514             : struct arch_elf_state {
     515             : };
     516             : 
     517             : #define INIT_ARCH_ELF_STATE {}
     518             : 
     519             : /**
     520             :  * arch_elf_pt_proc() - check a PT_LOPROC..PT_HIPROC ELF program header
     521             :  * @ehdr:       The main ELF header
     522             :  * @phdr:       The program header to check
     523             :  * @elf:        The open ELF file
     524             :  * @is_interp:  True if the phdr is from the interpreter of the ELF being
     525             :  *              loaded, else false.
     526             :  * @state:      Architecture-specific state preserved throughout the process
     527             :  *              of loading the ELF.
     528             :  *
     529             :  * Inspects the program header phdr to validate its correctness and/or
     530             :  * suitability for the system. Called once per ELF program header in the
     531             :  * range PT_LOPROC to PT_HIPROC, for both the ELF being loaded and its
     532             :  * interpreter.
     533             :  *
     534             :  * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load
     535             :  *         with that return code.
     536             :  */
     537             : static inline int arch_elf_pt_proc(struct elfhdr *ehdr,
     538             :                                    struct elf_phdr *phdr,
     539             :                                    struct file *elf, bool is_interp,
     540             :                                    struct arch_elf_state *state)
     541             : {
     542             :         /* Dummy implementation, always proceed */
     543             :         return 0;
     544             : }
     545             : 
     546             : /**
     547             :  * arch_check_elf() - check an ELF executable
     548             :  * @ehdr:       The main ELF header
     549             :  * @has_interp: True if the ELF has an interpreter, else false.
     550             :  * @interp_ehdr: The interpreter's ELF header
     551             :  * @state:      Architecture-specific state preserved throughout the process
     552             :  *              of loading the ELF.
     553             :  *
     554             :  * Provides a final opportunity for architecture code to reject the loading
     555             :  * of the ELF & cause an exec syscall to return an error. This is called after
     556             :  * all program headers to be checked by arch_elf_pt_proc have been.
     557             :  *
     558             :  * Return: Zero to proceed with the ELF load, non-zero to fail the ELF load
     559             :  *         with that return code.
     560             :  */
     561        1129 : static inline int arch_check_elf(struct elfhdr *ehdr, bool has_interp,
     562             :                                  struct elfhdr *interp_ehdr,
     563             :                                  struct arch_elf_state *state)
     564             : {
     565             :         /* Dummy implementation, always proceed */
     566        1129 :         return 0;
     567             : }
     568             : 
     569             : #endif /* !CONFIG_ARCH_BINFMT_ELF_STATE */
     570             : 
     571        9022 : static inline int make_prot(u32 p_flags, struct arch_elf_state *arch_state,
     572             :                             bool has_interp, bool is_interp)
     573             : {
     574        9022 :         int prot = 0;
     575             : 
     576        9022 :         if (p_flags & PF_R)
     577        9022 :                 prot |= PROT_READ;
     578        9022 :         if (p_flags & PF_W)
     579        2256 :                 prot |= PROT_WRITE;
     580        9022 :         if (p_flags & PF_X)
     581        2256 :                 prot |= PROT_EXEC;
     582             : 
     583        9022 :         return arch_elf_adjust_prot(prot, arch_state, has_interp, is_interp);
     584             : }
     585             : 
     586             : /* This is much more generalized than the library routine read function,
     587             :    so we keep this separate.  Technically the library read function
     588             :    is only provided so that we can read a.out libraries that have
     589             :    an ELF header */
     590             : 
     591        1127 : static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
     592             :                 struct file *interpreter,
     593             :                 unsigned long no_base, struct elf_phdr *interp_elf_phdata,
     594             :                 struct arch_elf_state *arch_state)
     595             : {
     596        1127 :         struct elf_phdr *eppnt;
     597        1127 :         unsigned long load_addr = 0;
     598        1127 :         int load_addr_set = 0;
     599        1127 :         unsigned long last_bss = 0, elf_bss = 0;
     600        1127 :         int bss_prot = 0;
     601        1127 :         unsigned long error = ~0UL;
     602        1127 :         unsigned long total_size;
     603        1127 :         int i;
     604             : 
     605             :         /* First of all, some simple consistency checks */
     606        1127 :         if (interp_elf_ex->e_type != ET_EXEC &&
     607             :             interp_elf_ex->e_type != ET_DYN)
     608           0 :                 goto out;
     609        1127 :         if (!elf_check_arch(interp_elf_ex) ||
     610             :             elf_check_fdpic(interp_elf_ex))
     611           0 :                 goto out;
     612        1127 :         if (!interpreter->f_op->mmap)
     613           0 :                 goto out;
     614             : 
     615        1127 :         total_size = total_mapping_size(interp_elf_phdata,
     616        1127 :                                         interp_elf_ex->e_phnum);
     617        1127 :         if (!total_size) {
     618           0 :                 error = -EINVAL;
     619           0 :                 goto out;
     620             :         }
     621             : 
     622             :         eppnt = interp_elf_phdata;
     623       11270 :         for (i = 0; i < interp_elf_ex->e_phnum; i++, eppnt++) {
     624       10143 :                 if (eppnt->p_type == PT_LOAD) {
     625        4508 :                         int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
     626        4508 :                         int elf_prot = make_prot(eppnt->p_flags, arch_state,
     627             :                                                  true, true);
     628        4508 :                         unsigned long vaddr = 0;
     629        4508 :                         unsigned long k, map_addr;
     630             : 
     631        4508 :                         vaddr = eppnt->p_vaddr;
     632        4508 :                         if (interp_elf_ex->e_type == ET_EXEC || load_addr_set)
     633             :                                 elf_type |= MAP_FIXED_NOREPLACE;
     634        1127 :                         else if (no_base && interp_elf_ex->e_type == ET_DYN)
     635        1127 :                                 load_addr = -vaddr;
     636             : 
     637        4508 :                         map_addr = elf_map(interpreter, load_addr + vaddr,
     638             :                                         eppnt, elf_prot, elf_type, total_size);
     639        4508 :                         total_size = 0;
     640        4508 :                         error = map_addr;
     641        4508 :                         if (BAD_ADDR(map_addr))
     642           0 :                                 goto out;
     643             : 
     644        4508 :                         if (!load_addr_set &&
     645        1127 :                             interp_elf_ex->e_type == ET_DYN) {
     646        1127 :                                 load_addr = map_addr - ELF_PAGESTART(vaddr);
     647        1127 :                                 load_addr_set = 1;
     648             :                         }
     649             : 
     650             :                         /*
     651             :                          * Check to see if the section's size will overflow the
     652             :                          * allowed task size. Note that p_filesz must always be
     653             :                          * <= p_memsize so it's only necessary to check p_memsz.
     654             :                          */
     655        4508 :                         k = load_addr + eppnt->p_vaddr;
     656        4508 :                         if (BAD_ADDR(k) ||
     657        9016 :                             eppnt->p_filesz > eppnt->p_memsz ||
     658        4508 :                             eppnt->p_memsz > TASK_SIZE ||
     659        4508 :                             TASK_SIZE - eppnt->p_memsz < k) {
     660           0 :                                 error = -ENOMEM;
     661           0 :                                 goto out;
     662             :                         }
     663             : 
     664             :                         /*
     665             :                          * Find the end of the file mapping for this phdr, and
     666             :                          * keep track of the largest address we see for this.
     667             :                          */
     668        4508 :                         k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
     669        4508 :                         if (k > elf_bss)
     670             :                                 elf_bss = k;
     671             : 
     672             :                         /*
     673             :                          * Do the same thing for the memory mapping - between
     674             :                          * elf_bss and last_bss is the bss section.
     675             :                          */
     676        4508 :                         k = load_addr + eppnt->p_vaddr + eppnt->p_memsz;
     677        4508 :                         if (k > last_bss) {
     678        4508 :                                 last_bss = k;
     679        4508 :                                 bss_prot = elf_prot;
     680             :                         }
     681             :                 }
     682             :         }
     683             : 
     684             :         /*
     685             :          * Now fill out the bss section: first pad the last page from
     686             :          * the file up to the page boundary, and zero it from elf_bss
     687             :          * up to the end of the page.
     688             :          */
     689        1127 :         if (padzero(elf_bss)) {
     690           0 :                 error = -EFAULT;
     691           0 :                 goto out;
     692             :         }
     693             :         /*
     694             :          * Next, align both the file and mem bss up to the page size,
     695             :          * since this is where elf_bss was just zeroed up to, and where
     696             :          * last_bss will end after the vm_brk_flags() below.
     697             :          */
     698        1127 :         elf_bss = ELF_PAGEALIGN(elf_bss);
     699        1127 :         last_bss = ELF_PAGEALIGN(last_bss);
     700             :         /* Finally, if there is still more bss to allocate, do it. */
     701        1127 :         if (last_bss > elf_bss) {
     702        1127 :                 error = vm_brk_flags(elf_bss, last_bss - elf_bss,
     703             :                                 bss_prot & PROT_EXEC ? VM_EXEC : 0);
     704        1127 :                 if (error)
     705           0 :                         goto out;
     706             :         }
     707             : 
     708             :         error = load_addr;
     709        1127 : out:
     710        1127 :         return error;
     711             : }
     712             : 
     713             : /*
     714             :  * These are the functions used to load ELF style executables and shared
     715             :  * libraries.  There is no binary dependent code anywhere else.
     716             :  */
     717             : 
     718             : static int parse_elf_property(const char *data, size_t *off, size_t datasz,
     719             :                               struct arch_elf_state *arch,
     720             :                               bool have_prev_type, u32 *prev_type)
     721             : {
     722             :         size_t o, step;
     723             :         const struct gnu_property *pr;
     724             :         int ret;
     725             : 
     726             :         if (*off == datasz)
     727             :                 return -ENOENT;
     728             : 
     729             :         if (WARN_ON_ONCE(*off > datasz || *off % ELF_GNU_PROPERTY_ALIGN))
     730             :                 return -EIO;
     731             :         o = *off;
     732             :         datasz -= *off;
     733             : 
     734             :         if (datasz < sizeof(*pr))
     735             :                 return -ENOEXEC;
     736             :         pr = (const struct gnu_property *)(data + o);
     737             :         o += sizeof(*pr);
     738             :         datasz -= sizeof(*pr);
     739             : 
     740             :         if (pr->pr_datasz > datasz)
     741             :                 return -ENOEXEC;
     742             : 
     743             :         WARN_ON_ONCE(o % ELF_GNU_PROPERTY_ALIGN);
     744             :         step = round_up(pr->pr_datasz, ELF_GNU_PROPERTY_ALIGN);
     745             :         if (step > datasz)
     746             :                 return -ENOEXEC;
     747             : 
     748             :         /* Properties are supposed to be unique and sorted on pr_type: */
     749             :         if (have_prev_type && pr->pr_type <= *prev_type)
     750             :                 return -ENOEXEC;
     751             :         *prev_type = pr->pr_type;
     752             : 
     753             :         ret = arch_parse_elf_property(pr->pr_type, data + o,
     754             :                                       pr->pr_datasz, ELF_COMPAT, arch);
     755             :         if (ret)
     756             :                 return ret;
     757             : 
     758             :         *off = o + step;
     759             :         return 0;
     760             : }
     761             : 
     762             : #define NOTE_DATA_SZ SZ_1K
     763             : #define GNU_PROPERTY_TYPE_0_NAME "GNU"
     764             : #define NOTE_NAME_SZ (sizeof(GNU_PROPERTY_TYPE_0_NAME))
     765             : 
     766        1129 : static int parse_elf_properties(struct file *f, const struct elf_phdr *phdr,
     767             :                                 struct arch_elf_state *arch)
     768             : {
     769        1129 :         union {
     770             :                 struct elf_note nhdr;
     771             :                 char data[NOTE_DATA_SZ];
     772             :         } note;
     773        1129 :         loff_t pos;
     774        1129 :         ssize_t n;
     775        1129 :         size_t off, datasz;
     776        1129 :         int ret;
     777        1129 :         bool have_prev_type;
     778        1129 :         u32 prev_type;
     779             : 
     780        1129 :         if (!IS_ENABLED(CONFIG_ARCH_USE_GNU_PROPERTY) || !phdr)
     781        1129 :                 return 0;
     782             : 
     783             :         /* load_elf_binary() shouldn't call us unless this is true... */
     784             :         if (WARN_ON_ONCE(phdr->p_type != PT_GNU_PROPERTY))
     785             :                 return -ENOEXEC;
     786             : 
     787             :         /* If the properties are crazy large, that's too bad (for now): */
     788             :         if (phdr->p_filesz > sizeof(note))
     789             :                 return -ENOEXEC;
     790             : 
     791             :         pos = phdr->p_offset;
     792             :         n = kernel_read(f, &note, phdr->p_filesz, &pos);
     793             : 
     794             :         BUILD_BUG_ON(sizeof(note) < sizeof(note.nhdr) + NOTE_NAME_SZ);
     795             :         if (n < 0 || n < sizeof(note.nhdr) + NOTE_NAME_SZ)
     796             :                 return -EIO;
     797             : 
     798             :         if (note.nhdr.n_type != NT_GNU_PROPERTY_TYPE_0 ||
     799             :             note.nhdr.n_namesz != NOTE_NAME_SZ ||
     800             :             strncmp(note.data + sizeof(note.nhdr),
     801             :                     GNU_PROPERTY_TYPE_0_NAME, n - sizeof(note.nhdr)))
     802             :                 return -ENOEXEC;
     803             : 
     804             :         off = round_up(sizeof(note.nhdr) + NOTE_NAME_SZ,
     805             :                        ELF_GNU_PROPERTY_ALIGN);
     806             :         if (off > n)
     807             :                 return -ENOEXEC;
     808             : 
     809             :         if (note.nhdr.n_descsz > n - off)
     810             :                 return -ENOEXEC;
     811             :         datasz = off + note.nhdr.n_descsz;
     812             : 
     813             :         have_prev_type = false;
     814             :         do {
     815             :                 ret = parse_elf_property(note.data, &off, datasz, arch,
     816             :                                          have_prev_type, &prev_type);
     817             :                 have_prev_type = true;
     818             :         } while (!ret);
     819             : 
     820             :         return ret == -ENOENT ? 0 : ret;
     821             : }
     822             : 
     823        1129 : static int load_elf_binary(struct linux_binprm *bprm)
     824             : {
     825        1129 :         struct file *interpreter = NULL; /* to shut gcc up */
     826        1129 :         unsigned long load_addr = 0, load_bias = 0;
     827        1129 :         int load_addr_set = 0;
     828        1129 :         unsigned long error;
     829        1129 :         struct elf_phdr *elf_ppnt, *elf_phdata, *interp_elf_phdata = NULL;
     830        1129 :         struct elf_phdr *elf_property_phdata = NULL;
     831        1129 :         unsigned long elf_bss, elf_brk;
     832        1129 :         int bss_prot = 0;
     833        1129 :         int retval, i;
     834        1129 :         unsigned long elf_entry;
     835        1129 :         unsigned long e_entry;
     836        1129 :         unsigned long interp_load_addr = 0;
     837        1129 :         unsigned long start_code, end_code, start_data, end_data;
     838        1129 :         unsigned long reloc_func_desc __maybe_unused = 0;
     839        1129 :         int executable_stack = EXSTACK_DEFAULT;
     840        1129 :         struct elfhdr *elf_ex = (struct elfhdr *)bprm->buf;
     841        1129 :         struct elfhdr *interp_elf_ex = NULL;
     842        1129 :         struct arch_elf_state arch_state = INIT_ARCH_ELF_STATE;
     843        1129 :         struct mm_struct *mm;
     844        1129 :         struct pt_regs *regs;
     845             : 
     846        1129 :         retval = -ENOEXEC;
     847             :         /* First of all, some simple consistency checks */
     848        1129 :         if (memcmp(elf_ex->e_ident, ELFMAG, SELFMAG) != 0)
     849           0 :                 goto out;
     850             : 
     851        1129 :         if (elf_ex->e_type != ET_EXEC && elf_ex->e_type != ET_DYN)
     852           0 :                 goto out;
     853        1129 :         if (!elf_check_arch(elf_ex))
     854           0 :                 goto out;
     855        1129 :         if (elf_check_fdpic(elf_ex))
     856             :                 goto out;
     857        1129 :         if (!bprm->file->f_op->mmap)
     858           0 :                 goto out;
     859             : 
     860        1129 :         elf_phdata = load_elf_phdrs(elf_ex, bprm->file);
     861        1129 :         if (!elf_phdata)
     862           0 :                 goto out;
     863             : 
     864             :         elf_ppnt = elf_phdata;
     865        2272 :         for (i = 0; i < elf_ex->e_phnum; i++, elf_ppnt++) {
     866        2270 :                 char *elf_interpreter;
     867             : 
     868        2270 :                 if (elf_ppnt->p_type == PT_GNU_PROPERTY) {
     869           0 :                         elf_property_phdata = elf_ppnt;
     870           0 :                         continue;
     871             :                 }
     872             : 
     873        2270 :                 if (elf_ppnt->p_type != PT_INTERP)
     874        1143 :                         continue;
     875             : 
     876             :                 /*
     877             :                  * This is the program interpreter used for shared libraries -
     878             :                  * for now assume that this is an a.out format binary.
     879             :                  */
     880        1127 :                 retval = -ENOEXEC;
     881        1127 :                 if (elf_ppnt->p_filesz > PATH_MAX || elf_ppnt->p_filesz < 2)
     882           0 :                         goto out_free_ph;
     883             : 
     884        1127 :                 retval = -ENOMEM;
     885        1127 :                 elf_interpreter = kmalloc(elf_ppnt->p_filesz, GFP_KERNEL);
     886        1127 :                 if (!elf_interpreter)
     887           0 :                         goto out_free_ph;
     888             : 
     889        2254 :                 retval = elf_read(bprm->file, elf_interpreter, elf_ppnt->p_filesz,
     890        1127 :                                   elf_ppnt->p_offset);
     891        1127 :                 if (retval < 0)
     892           0 :                         goto out_free_interp;
     893             :                 /* make sure path is NULL terminated */
     894        1127 :                 retval = -ENOEXEC;
     895        1127 :                 if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
     896           0 :                         goto out_free_interp;
     897             : 
     898        1127 :                 interpreter = open_exec(elf_interpreter);
     899        1127 :                 kfree(elf_interpreter);
     900        1127 :                 retval = PTR_ERR(interpreter);
     901        1127 :                 if (IS_ERR(interpreter))
     902           0 :                         goto out_free_ph;
     903             : 
     904             :                 /*
     905             :                  * If the binary is not readable then enforce mm->dumpable = 0
     906             :                  * regardless of the interpreter's permissions.
     907             :                  */
     908        1127 :                 would_dump(bprm, interpreter);
     909             : 
     910        1127 :                 interp_elf_ex = kmalloc(sizeof(*interp_elf_ex), GFP_KERNEL);
     911        1127 :                 if (!interp_elf_ex) {
     912           0 :                         retval = -ENOMEM;
     913           0 :                         goto out_free_ph;
     914             :                 }
     915             : 
     916             :                 /* Get the exec headers */
     917        1127 :                 retval = elf_read(interpreter, interp_elf_ex,
     918             :                                   sizeof(*interp_elf_ex), 0);
     919        1127 :                 if (retval < 0)
     920           0 :                         goto out_free_dentry;
     921             : 
     922             :                 break;
     923             : 
     924           0 : out_free_interp:
     925           0 :                 kfree(elf_interpreter);
     926           0 :                 goto out_free_ph;
     927             :         }
     928             : 
     929        1129 :         elf_ppnt = elf_phdata;
     930       13557 :         for (i = 0; i < elf_ex->e_phnum; i++, elf_ppnt++)
     931       12428 :                 switch (elf_ppnt->p_type) {
     932        1129 :                 case PT_GNU_STACK:
     933        1129 :                         if (elf_ppnt->p_flags & PF_X)
     934             :                                 executable_stack = EXSTACK_ENABLE_X;
     935             :                         else
     936             :                                 executable_stack = EXSTACK_DISABLE_X;
     937             :                         break;
     938             : 
     939             :                 case PT_LOPROC ... PT_HIPROC:
     940       12428 :                         retval = arch_elf_pt_proc(elf_ex, elf_ppnt,
     941             :                                                   bprm->file, false,
     942             :                                                   &arch_state);
     943             :                         if (retval)
     944             :                                 goto out_free_dentry;
     945             :                         break;
     946             :                 }
     947             : 
     948             :         /* Some simple consistency checks for the interpreter */
     949       13557 :         if (interpreter) {
     950        1127 :                 retval = -ELIBBAD;
     951             :                 /* Not an ELF interpreter */
     952        1127 :                 if (memcmp(interp_elf_ex->e_ident, ELFMAG, SELFMAG) != 0)
     953           0 :                         goto out_free_dentry;
     954             :                 /* Verify the interpreter has a valid arch */
     955        1127 :                 if (!elf_check_arch(interp_elf_ex) ||
     956             :                     elf_check_fdpic(interp_elf_ex))
     957           0 :                         goto out_free_dentry;
     958             : 
     959             :                 /* Load the interpreter program headers */
     960        1127 :                 interp_elf_phdata = load_elf_phdrs(interp_elf_ex,
     961             :                                                    interpreter);
     962        1127 :                 if (!interp_elf_phdata)
     963           0 :                         goto out_free_dentry;
     964             : 
     965             :                 /* Pass PT_LOPROC..PT_HIPROC headers to arch code */
     966             :                 elf_property_phdata = NULL;
     967             :                 elf_ppnt = interp_elf_phdata;
     968       11270 :                 for (i = 0; i < interp_elf_ex->e_phnum; i++, elf_ppnt++)
     969       10143 :                         switch (elf_ppnt->p_type) {
     970             :                         case PT_GNU_PROPERTY:
     971             :                                 elf_property_phdata = elf_ppnt;
     972             :                                 break;
     973             : 
     974             :                         case PT_LOPROC ... PT_HIPROC:
     975       10143 :                                 retval = arch_elf_pt_proc(interp_elf_ex,
     976             :                                                           elf_ppnt, interpreter,
     977             :                                                           true, &arch_state);
     978             :                                 if (retval)
     979             :                                         goto out_free_dentry;
     980             :                                 break;
     981             :                         }
     982       10143 :         }
     983             : 
     984        1129 :         retval = parse_elf_properties(interpreter ?: bprm->file,
     985             :                                       elf_property_phdata, &arch_state);
     986        1129 :         if (retval)
     987             :                 goto out_free_dentry;
     988             : 
     989             :         /*
     990             :          * Allow arch code to reject the ELF at this point, whilst it's
     991             :          * still possible to return an error to the code that invoked
     992             :          * the exec syscall.
     993             :          */
     994        1129 :         retval = arch_check_elf(elf_ex,
     995             :                                 !!interpreter, interp_elf_ex,
     996             :                                 &arch_state);
     997        1129 :         if (retval)
     998             :                 goto out_free_dentry;
     999             : 
    1000             :         /* Flush all traces of the currently running executable */
    1001        1129 :         retval = begin_new_exec(bprm);
    1002        1129 :         if (retval)
    1003           0 :                 goto out_free_dentry;
    1004             : 
    1005             :         /* Do this immediately, since STACK_TOP as used in setup_arg_pages
    1006             :            may depend on the personality.  */
    1007        1129 :         SET_PERSONALITY2(*elf_ex, &arch_state);
    1008        1129 :         if (elf_read_implies_exec(*elf_ex, executable_stack))
    1009           0 :                 current->personality |= READ_IMPLIES_EXEC;
    1010             : 
    1011        1129 :         if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
    1012        1129 :                 current->flags |= PF_RANDOMIZE;
    1013             : 
    1014        1129 :         setup_new_exec(bprm);
    1015             : 
    1016             :         /* Do this so that we can load the interpreter, if need be.  We will
    1017             :            change some of these later */
    1018        1129 :         retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP),
    1019             :                                  executable_stack);
    1020        1129 :         if (retval < 0)
    1021           0 :                 goto out_free_dentry;
    1022             :         
    1023             :         elf_bss = 0;
    1024             :         elf_brk = 0;
    1025             : 
    1026             :         start_code = ~0UL;
    1027             :         end_code = 0;
    1028             :         start_data = 0;
    1029             :         end_data = 0;
    1030             : 
    1031             :         /* Now we do a little grungy work by mmapping the ELF image into
    1032             :            the correct location in memory. */
    1033       13557 :         for(i = 0, elf_ppnt = elf_phdata;
    1034       13557 :             i < elf_ex->e_phnum; i++, elf_ppnt++) {
    1035       12428 :                 int elf_prot, elf_flags;
    1036       12428 :                 unsigned long k, vaddr;
    1037       12428 :                 unsigned long total_size = 0;
    1038       12428 :                 unsigned long alignment;
    1039             : 
    1040       12428 :                 if (elf_ppnt->p_type != PT_LOAD)
    1041        7914 :                         continue;
    1042             : 
    1043        4514 :                 if (unlikely (elf_brk > elf_bss)) {
    1044           0 :                         unsigned long nbyte;
    1045             :                     
    1046             :                         /* There was a PT_LOAD segment with p_memsz > p_filesz
    1047             :                            before this one. Map anonymous pages, if needed,
    1048             :                            and clear the area.  */
    1049           0 :                         retval = set_brk(elf_bss + load_bias,
    1050             :                                          elf_brk + load_bias,
    1051             :                                          bss_prot);
    1052           0 :                         if (retval)
    1053           0 :                                 goto out_free_dentry;
    1054           0 :                         nbyte = ELF_PAGEOFFSET(elf_bss);
    1055           0 :                         if (nbyte) {
    1056           0 :                                 nbyte = ELF_MIN_ALIGN - nbyte;
    1057           0 :                                 if (nbyte > elf_brk - elf_bss)
    1058             :                                         nbyte = elf_brk - elf_bss;
    1059           0 :                                 if (clear_user((void __user *)elf_bss +
    1060             :                                                         load_bias, nbyte)) {
    1061             :                                         /*
    1062             :                                          * This bss-zeroing can fail if the ELF
    1063             :                                          * file specifies odd protections. So
    1064             :                                          * we don't check the return value
    1065             :                                          */
    1066        4514 :                                 }
    1067             :                         }
    1068             :                 }
    1069             : 
    1070        4514 :                 elf_prot = make_prot(elf_ppnt->p_flags, &arch_state,
    1071             :                                      !!interpreter, false);
    1072             : 
    1073        4514 :                 elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
    1074             : 
    1075        4514 :                 vaddr = elf_ppnt->p_vaddr;
    1076             :                 /*
    1077             :                  * If we are loading ET_EXEC or we have already performed
    1078             :                  * the ET_DYN load_addr calculations, proceed normally.
    1079             :                  */
    1080        4514 :                 if (elf_ex->e_type == ET_EXEC || load_addr_set) {
    1081             :                         elf_flags |= MAP_FIXED;
    1082        1127 :                 } else if (elf_ex->e_type == ET_DYN) {
    1083             :                         /*
    1084             :                          * This logic is run once for the first LOAD Program
    1085             :                          * Header for ET_DYN binaries to calculate the
    1086             :                          * randomization (load_bias) for all the LOAD
    1087             :                          * Program Headers, and to calculate the entire
    1088             :                          * size of the ELF mapping (total_size). (Note that
    1089             :                          * load_addr_set is set to true later once the
    1090             :                          * initial mapping is performed.)
    1091             :                          *
    1092             :                          * There are effectively two types of ET_DYN
    1093             :                          * binaries: programs (i.e. PIE: ET_DYN with INTERP)
    1094             :                          * and loaders (ET_DYN without INTERP, since they
    1095             :                          * _are_ the ELF interpreter). The loaders must
    1096             :                          * be loaded away from programs since the program
    1097             :                          * may otherwise collide with the loader (especially
    1098             :                          * for ET_EXEC which does not have a randomized
    1099             :                          * position). For example to handle invocations of
    1100             :                          * "./ld.so someprog" to test out a new version of
    1101             :                          * the loader, the subsequent program that the
    1102             :                          * loader loads must avoid the loader itself, so
    1103             :                          * they cannot share the same load range. Sufficient
    1104             :                          * room for the brk must be allocated with the
    1105             :                          * loader as well, since brk must be available with
    1106             :                          * the loader.
    1107             :                          *
    1108             :                          * Therefore, programs are loaded offset from
    1109             :                          * ELF_ET_DYN_BASE and loaders are loaded into the
    1110             :                          * independently randomized mmap region (0 load_bias
    1111             :                          * without MAP_FIXED).
    1112             :                          */
    1113        1127 :                         if (interpreter) {
    1114        1127 :                                 load_bias = ELF_ET_DYN_BASE;
    1115        1127 :                                 if (current->flags & PF_RANDOMIZE)
    1116        1127 :                                         load_bias += arch_mmap_rnd();
    1117        1127 :                                 alignment = maximum_alignment(elf_phdata, elf_ex->e_phnum);
    1118        1127 :                                 if (alignment)
    1119        1127 :                                         load_bias &= ~(alignment - 1);
    1120             :                                 elf_flags |= MAP_FIXED;
    1121             :                         } else
    1122             :                                 load_bias = 0;
    1123             : 
    1124             :                         /*
    1125             :                          * Since load_bias is used for all subsequent loading
    1126             :                          * calculations, we must lower it by the first vaddr
    1127             :                          * so that the remaining calculations based on the
    1128             :                          * ELF vaddrs will be correctly offset. The result
    1129             :                          * is then page aligned.
    1130             :                          */
    1131        1127 :                         load_bias = ELF_PAGESTART(load_bias - vaddr);
    1132             : 
    1133        1127 :                         total_size = total_mapping_size(elf_phdata,
    1134        1127 :                                                         elf_ex->e_phnum);
    1135        1127 :                         if (!total_size) {
    1136           0 :                                 retval = -EINVAL;
    1137           0 :                                 goto out_free_dentry;
    1138             :                         }
    1139             :                 }
    1140             : 
    1141        4514 :                 error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
    1142             :                                 elf_prot, elf_flags, total_size);
    1143        4514 :                 if (BAD_ADDR(error)) {
    1144           0 :                         retval = IS_ERR((void *)error) ?
    1145           0 :                                 PTR_ERR((void*)error) : -EINVAL;
    1146           0 :                         goto out_free_dentry;
    1147             :                 }
    1148             : 
    1149        4514 :                 if (!load_addr_set) {
    1150        1129 :                         load_addr_set = 1;
    1151        1129 :                         load_addr = (elf_ppnt->p_vaddr - elf_ppnt->p_offset);
    1152        1129 :                         if (elf_ex->e_type == ET_DYN) {
    1153        1127 :                                 load_bias += error -
    1154        1127 :                                              ELF_PAGESTART(load_bias + vaddr);
    1155        1127 :                                 load_addr += load_bias;
    1156        1127 :                                 reloc_func_desc = load_bias;
    1157             :                         }
    1158             :                 }
    1159        4514 :                 k = elf_ppnt->p_vaddr;
    1160        4514 :                 if ((elf_ppnt->p_flags & PF_X) && k < start_code)
    1161             :                         start_code = k;
    1162        4514 :                 if (start_data < k)
    1163             :                         start_data = k;
    1164             : 
    1165             :                 /*
    1166             :                  * Check to see if the section's size will overflow the
    1167             :                  * allowed task size. Note that p_filesz must always be
    1168             :                  * <= p_memsz so it is only necessary to check p_memsz.
    1169             :                  */
    1170        9028 :                 if (BAD_ADDR(k) || elf_ppnt->p_filesz > elf_ppnt->p_memsz ||
    1171        4514 :                     elf_ppnt->p_memsz > TASK_SIZE ||
    1172        4514 :                     TASK_SIZE - elf_ppnt->p_memsz < k) {
    1173             :                         /* set_brk can never work. Avoid overflows. */
    1174           0 :                         retval = -EINVAL;
    1175           0 :                         goto out_free_dentry;
    1176             :                 }
    1177             : 
    1178        4514 :                 k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
    1179             : 
    1180        4514 :                 if (k > elf_bss)
    1181             :                         elf_bss = k;
    1182        4514 :                 if ((elf_ppnt->p_flags & PF_X) && end_code < k)
    1183             :                         end_code = k;
    1184        4514 :                 if (end_data < k)
    1185             :                         end_data = k;
    1186        4514 :                 k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
    1187        4514 :                 if (k > elf_brk) {
    1188        4514 :                         bss_prot = elf_prot;
    1189        4514 :                         elf_brk = k;
    1190             :                 }
    1191             :         }
    1192             : 
    1193        1129 :         e_entry = elf_ex->e_entry + load_bias;
    1194        1129 :         elf_bss += load_bias;
    1195        1129 :         elf_brk += load_bias;
    1196        1129 :         start_code += load_bias;
    1197        1129 :         end_code += load_bias;
    1198        1129 :         start_data += load_bias;
    1199        1129 :         end_data += load_bias;
    1200             : 
    1201             :         /* Calling set_brk effectively mmaps the pages that we need
    1202             :          * for the bss and break sections.  We must do this before
    1203             :          * mapping in the interpreter, to make sure it doesn't wind
    1204             :          * up getting placed where the bss needs to go.
    1205             :          */
    1206        1129 :         retval = set_brk(elf_bss, elf_brk, bss_prot);
    1207        1129 :         if (retval)
    1208           0 :                 goto out_free_dentry;
    1209        1129 :         if (likely(elf_bss != elf_brk) && unlikely(padzero(elf_bss))) {
    1210           0 :                 retval = -EFAULT; /* Nobody gets to see this, but.. */
    1211           0 :                 goto out_free_dentry;
    1212             :         }
    1213             : 
    1214        1129 :         if (interpreter) {
    1215        1127 :                 elf_entry = load_elf_interp(interp_elf_ex,
    1216             :                                             interpreter,
    1217             :                                             load_bias, interp_elf_phdata,
    1218             :                                             &arch_state);
    1219        1127 :                 if (!IS_ERR((void *)elf_entry)) {
    1220             :                         /*
    1221             :                          * load_elf_interp() returns relocation
    1222             :                          * adjustment
    1223             :                          */
    1224        1127 :                         interp_load_addr = elf_entry;
    1225        1127 :                         elf_entry += interp_elf_ex->e_entry;
    1226             :                 }
    1227        1127 :                 if (BAD_ADDR(elf_entry)) {
    1228           0 :                         retval = IS_ERR((void *)elf_entry) ?
    1229           0 :                                         (int)elf_entry : -EINVAL;
    1230           0 :                         goto out_free_dentry;
    1231             :                 }
    1232        1127 :                 reloc_func_desc = interp_load_addr;
    1233             : 
    1234        1127 :                 allow_write_access(interpreter);
    1235        1127 :                 fput(interpreter);
    1236             : 
    1237        1127 :                 kfree(interp_elf_ex);
    1238        1127 :                 kfree(interp_elf_phdata);
    1239             :         } else {
    1240           2 :                 elf_entry = e_entry;
    1241           2 :                 if (BAD_ADDR(elf_entry)) {
    1242           0 :                         retval = -EINVAL;
    1243           0 :                         goto out_free_dentry;
    1244             :                 }
    1245             :         }
    1246             : 
    1247        1129 :         kfree(elf_phdata);
    1248             : 
    1249        1129 :         set_binfmt(&elf_format);
    1250             : 
    1251             : #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
    1252        1129 :         retval = ARCH_SETUP_ADDITIONAL_PAGES(bprm, elf_ex, !!interpreter);
    1253        1129 :         if (retval < 0)
    1254           0 :                 goto out;
    1255             : #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
    1256             : 
    1257        1129 :         retval = create_elf_tables(bprm, elf_ex,
    1258             :                           load_addr, interp_load_addr, e_entry);
    1259        1129 :         if (retval < 0)
    1260           0 :                 goto out;
    1261             : 
    1262        1129 :         mm = current->mm;
    1263        1129 :         mm->end_code = end_code;
    1264        1129 :         mm->start_code = start_code;
    1265        1129 :         mm->start_data = start_data;
    1266        1129 :         mm->end_data = end_data;
    1267        1129 :         mm->start_stack = bprm->p;
    1268             : 
    1269        1129 :         if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) {
    1270             :                 /*
    1271             :                  * For architectures with ELF randomization, when executing
    1272             :                  * a loader directly (i.e. no interpreter listed in ELF
    1273             :                  * headers), move the brk area out of the mmap region
    1274             :                  * (since it grows up, and may collide early with the stack
    1275             :                  * growing down), and into the unused ELF_ET_DYN_BASE region.
    1276             :                  */
    1277        1129 :                 if (IS_ENABLED(CONFIG_ARCH_HAS_ELF_RANDOMIZE) &&
    1278        1129 :                     elf_ex->e_type == ET_DYN && !interpreter) {
    1279           0 :                         mm->brk = mm->start_brk = ELF_ET_DYN_BASE;
    1280             :                 }
    1281             : 
    1282        1129 :                 mm->brk = mm->start_brk = arch_randomize_brk(mm);
    1283             : #ifdef compat_brk_randomized
    1284             :                 current->brk_randomized = 1;
    1285             : #endif
    1286             :         }
    1287             : 
    1288        1129 :         if (current->personality & MMAP_PAGE_ZERO) {
    1289             :                 /* Why this, you ask???  Well SVr4 maps page 0 as read-only,
    1290             :                    and some applications "depend" upon this behavior.
    1291             :                    Since we do not have the power to recompile these, we
    1292             :                    emulate the SVr4 behavior. Sigh. */
    1293           0 :                 error = vm_mmap(NULL, 0, PAGE_SIZE, PROT_READ | PROT_EXEC,
    1294             :                                 MAP_FIXED | MAP_PRIVATE, 0);
    1295             :         }
    1296             : 
    1297        1129 :         regs = current_pt_regs();
    1298             : #ifdef ELF_PLAT_INIT
    1299             :         /*
    1300             :          * The ABI may specify that certain registers be set up in special
    1301             :          * ways (on i386 %edx is the address of a DT_FINI function, for
    1302             :          * example.  In addition, it may also specify (eg, PowerPC64 ELF)
    1303             :          * that the e_entry field is the address of the function descriptor
    1304             :          * for the startup routine, rather than the address of the startup
    1305             :          * routine itself.  This macro performs whatever initialization to
    1306             :          * the regs structure is required as well as any relocations to the
    1307             :          * function descriptor entries when executing dynamically links apps.
    1308             :          */
    1309        1129 :         ELF_PLAT_INIT(regs, reloc_func_desc);
    1310             : #endif
    1311             : 
    1312        1129 :         finalize_exec(bprm);
    1313        1129 :         START_THREAD(elf_ex, regs, elf_entry, bprm->p);
    1314        1129 :         retval = 0;
    1315        1129 : out:
    1316        1129 :         return retval;
    1317             : 
    1318             :         /* error cleanup */
    1319           0 : out_free_dentry:
    1320           0 :         kfree(interp_elf_ex);
    1321           0 :         kfree(interp_elf_phdata);
    1322           0 :         allow_write_access(interpreter);
    1323           0 :         if (interpreter)
    1324           0 :                 fput(interpreter);
    1325           0 : out_free_ph:
    1326           0 :         kfree(elf_phdata);
    1327           0 :         goto out;
    1328             : }
    1329             : 
    1330             : #ifdef CONFIG_USELIB
    1331             : /* This is really simpleminded and specialized - we are loading an
    1332             :    a.out library that is given an ELF header. */
    1333             : static int load_elf_library(struct file *file)
    1334             : {
    1335             :         struct elf_phdr *elf_phdata;
    1336             :         struct elf_phdr *eppnt;
    1337             :         unsigned long elf_bss, bss, len;
    1338             :         int retval, error, i, j;
    1339             :         struct elfhdr elf_ex;
    1340             : 
    1341             :         error = -ENOEXEC;
    1342             :         retval = elf_read(file, &elf_ex, sizeof(elf_ex), 0);
    1343             :         if (retval < 0)
    1344             :                 goto out;
    1345             : 
    1346             :         if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
    1347             :                 goto out;
    1348             : 
    1349             :         /* First of all, some simple consistency checks */
    1350             :         if (elf_ex.e_type != ET_EXEC || elf_ex.e_phnum > 2 ||
    1351             :             !elf_check_arch(&elf_ex) || !file->f_op->mmap)
    1352             :                 goto out;
    1353             :         if (elf_check_fdpic(&elf_ex))
    1354             :                 goto out;
    1355             : 
    1356             :         /* Now read in all of the header information */
    1357             : 
    1358             :         j = sizeof(struct elf_phdr) * elf_ex.e_phnum;
    1359             :         /* j < ELF_MIN_ALIGN because elf_ex.e_phnum <= 2 */
    1360             : 
    1361             :         error = -ENOMEM;
    1362             :         elf_phdata = kmalloc(j, GFP_KERNEL);
    1363             :         if (!elf_phdata)
    1364             :                 goto out;
    1365             : 
    1366             :         eppnt = elf_phdata;
    1367             :         error = -ENOEXEC;
    1368             :         retval = elf_read(file, eppnt, j, elf_ex.e_phoff);
    1369             :         if (retval < 0)
    1370             :                 goto out_free_ph;
    1371             : 
    1372             :         for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
    1373             :                 if ((eppnt + i)->p_type == PT_LOAD)
    1374             :                         j++;
    1375             :         if (j != 1)
    1376             :                 goto out_free_ph;
    1377             : 
    1378             :         while (eppnt->p_type != PT_LOAD)
    1379             :                 eppnt++;
    1380             : 
    1381             :         /* Now use mmap to map the library into memory. */
    1382             :         error = vm_mmap(file,
    1383             :                         ELF_PAGESTART(eppnt->p_vaddr),
    1384             :                         (eppnt->p_filesz +
    1385             :                          ELF_PAGEOFFSET(eppnt->p_vaddr)),
    1386             :                         PROT_READ | PROT_WRITE | PROT_EXEC,
    1387             :                         MAP_FIXED_NOREPLACE | MAP_PRIVATE | MAP_DENYWRITE,
    1388             :                         (eppnt->p_offset -
    1389             :                          ELF_PAGEOFFSET(eppnt->p_vaddr)));
    1390             :         if (error != ELF_PAGESTART(eppnt->p_vaddr))
    1391             :                 goto out_free_ph;
    1392             : 
    1393             :         elf_bss = eppnt->p_vaddr + eppnt->p_filesz;
    1394             :         if (padzero(elf_bss)) {
    1395             :                 error = -EFAULT;
    1396             :                 goto out_free_ph;
    1397             :         }
    1398             : 
    1399             :         len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr);
    1400             :         bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr);
    1401             :         if (bss > len) {
    1402             :                 error = vm_brk(len, bss - len);
    1403             :                 if (error)
    1404             :                         goto out_free_ph;
    1405             :         }
    1406             :         error = 0;
    1407             : 
    1408             : out_free_ph:
    1409             :         kfree(elf_phdata);
    1410             : out:
    1411             :         return error;
    1412             : }
    1413             : #endif /* #ifdef CONFIG_USELIB */
    1414             : 
    1415             : #ifdef CONFIG_ELF_CORE
    1416             : /*
    1417             :  * ELF core dumper
    1418             :  *
    1419             :  * Modelled on fs/exec.c:aout_core_dump()
    1420             :  * Jeremy Fitzhardinge <jeremy@sw.oz.au>
    1421             :  */
    1422             : 
    1423             : /* An ELF note in memory */
    1424             : struct memelfnote
    1425             : {
    1426             :         const char *name;
    1427             :         int type;
    1428             :         unsigned int datasz;
    1429             :         void *data;
    1430             : };
    1431             : 
    1432             : static int notesize(struct memelfnote *en)
    1433             : {
    1434             :         int sz;
    1435             : 
    1436             :         sz = sizeof(struct elf_note);
    1437             :         sz += roundup(strlen(en->name) + 1, 4);
    1438             :         sz += roundup(en->datasz, 4);
    1439             : 
    1440             :         return sz;
    1441             : }
    1442             : 
    1443             : static int writenote(struct memelfnote *men, struct coredump_params *cprm)
    1444             : {
    1445             :         struct elf_note en;
    1446             :         en.n_namesz = strlen(men->name) + 1;
    1447             :         en.n_descsz = men->datasz;
    1448             :         en.n_type = men->type;
    1449             : 
    1450             :         return dump_emit(cprm, &en, sizeof(en)) &&
    1451             :             dump_emit(cprm, men->name, en.n_namesz) && dump_align(cprm, 4) &&
    1452             :             dump_emit(cprm, men->data, men->datasz) && dump_align(cprm, 4);
    1453             : }
    1454             : 
    1455             : static void fill_elf_header(struct elfhdr *elf, int segs,
    1456             :                             u16 machine, u32 flags)
    1457             : {
    1458             :         memset(elf, 0, sizeof(*elf));
    1459             : 
    1460             :         memcpy(elf->e_ident, ELFMAG, SELFMAG);
    1461             :         elf->e_ident[EI_CLASS] = ELF_CLASS;
    1462             :         elf->e_ident[EI_DATA] = ELF_DATA;
    1463             :         elf->e_ident[EI_VERSION] = EV_CURRENT;
    1464             :         elf->e_ident[EI_OSABI] = ELF_OSABI;
    1465             : 
    1466             :         elf->e_type = ET_CORE;
    1467             :         elf->e_machine = machine;
    1468             :         elf->e_version = EV_CURRENT;
    1469             :         elf->e_phoff = sizeof(struct elfhdr);
    1470             :         elf->e_flags = flags;
    1471             :         elf->e_ehsize = sizeof(struct elfhdr);
    1472             :         elf->e_phentsize = sizeof(struct elf_phdr);
    1473             :         elf->e_phnum = segs;
    1474             : }
    1475             : 
    1476             : static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset)
    1477             : {
    1478             :         phdr->p_type = PT_NOTE;
    1479             :         phdr->p_offset = offset;
    1480             :         phdr->p_vaddr = 0;
    1481             :         phdr->p_paddr = 0;
    1482             :         phdr->p_filesz = sz;
    1483             :         phdr->p_memsz = 0;
    1484             :         phdr->p_flags = 0;
    1485             :         phdr->p_align = 0;
    1486             : }
    1487             : 
    1488             : static void fill_note(struct memelfnote *note, const char *name, int type, 
    1489             :                 unsigned int sz, void *data)
    1490             : {
    1491             :         note->name = name;
    1492             :         note->type = type;
    1493             :         note->datasz = sz;
    1494             :         note->data = data;
    1495             : }
    1496             : 
    1497             : /*
    1498             :  * fill up all the fields in prstatus from the given task struct, except
    1499             :  * registers which need to be filled up separately.
    1500             :  */
    1501             : static void fill_prstatus(struct elf_prstatus_common *prstatus,
    1502             :                 struct task_struct *p, long signr)
    1503             : {
    1504             :         prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
    1505             :         prstatus->pr_sigpend = p->pending.signal.sig[0];
    1506             :         prstatus->pr_sighold = p->blocked.sig[0];
    1507             :         rcu_read_lock();
    1508             :         prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
    1509             :         rcu_read_unlock();
    1510             :         prstatus->pr_pid = task_pid_vnr(p);
    1511             :         prstatus->pr_pgrp = task_pgrp_vnr(p);
    1512             :         prstatus->pr_sid = task_session_vnr(p);
    1513             :         if (thread_group_leader(p)) {
    1514             :                 struct task_cputime cputime;
    1515             : 
    1516             :                 /*
    1517             :                  * This is the record for the group leader.  It shows the
    1518             :                  * group-wide total, not its individual thread total.
    1519             :                  */
    1520             :                 thread_group_cputime(p, &cputime);
    1521             :                 prstatus->pr_utime = ns_to_kernel_old_timeval(cputime.utime);
    1522             :                 prstatus->pr_stime = ns_to_kernel_old_timeval(cputime.stime);
    1523             :         } else {
    1524             :                 u64 utime, stime;
    1525             : 
    1526             :                 task_cputime(p, &utime, &stime);
    1527             :                 prstatus->pr_utime = ns_to_kernel_old_timeval(utime);
    1528             :                 prstatus->pr_stime = ns_to_kernel_old_timeval(stime);
    1529             :         }
    1530             : 
    1531             :         prstatus->pr_cutime = ns_to_kernel_old_timeval(p->signal->cutime);
    1532             :         prstatus->pr_cstime = ns_to_kernel_old_timeval(p->signal->cstime);
    1533             : }
    1534             : 
    1535             : static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
    1536             :                        struct mm_struct *mm)
    1537             : {
    1538             :         const struct cred *cred;
    1539             :         unsigned int i, len;
    1540             :         
    1541             :         /* first copy the parameters from user space */
    1542             :         memset(psinfo, 0, sizeof(struct elf_prpsinfo));
    1543             : 
    1544             :         len = mm->arg_end - mm->arg_start;
    1545             :         if (len >= ELF_PRARGSZ)
    1546             :                 len = ELF_PRARGSZ-1;
    1547             :         if (copy_from_user(&psinfo->pr_psargs,
    1548             :                            (const char __user *)mm->arg_start, len))
    1549             :                 return -EFAULT;
    1550             :         for(i = 0; i < len; i++)
    1551             :                 if (psinfo->pr_psargs[i] == 0)
    1552             :                         psinfo->pr_psargs[i] = ' ';
    1553             :         psinfo->pr_psargs[len] = 0;
    1554             : 
    1555             :         rcu_read_lock();
    1556             :         psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
    1557             :         rcu_read_unlock();
    1558             :         psinfo->pr_pid = task_pid_vnr(p);
    1559             :         psinfo->pr_pgrp = task_pgrp_vnr(p);
    1560             :         psinfo->pr_sid = task_session_vnr(p);
    1561             : 
    1562             :         i = p->state ? ffz(~p->state) + 1 : 0;
    1563             :         psinfo->pr_state = i;
    1564             :         psinfo->pr_sname = (i > 5) ? '.' : "RSDTZW"[i];
    1565             :         psinfo->pr_zomb = psinfo->pr_sname == 'Z';
    1566             :         psinfo->pr_nice = task_nice(p);
    1567             :         psinfo->pr_flag = p->flags;
    1568             :         rcu_read_lock();
    1569             :         cred = __task_cred(p);
    1570             :         SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid));
    1571             :         SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid));
    1572             :         rcu_read_unlock();
    1573             :         strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
    1574             :         
    1575             :         return 0;
    1576             : }
    1577             : 
    1578             : static void fill_auxv_note(struct memelfnote *note, struct mm_struct *mm)
    1579             : {
    1580             :         elf_addr_t *auxv = (elf_addr_t *) mm->saved_auxv;
    1581             :         int i = 0;
    1582             :         do
    1583             :                 i += 2;
    1584             :         while (auxv[i - 2] != AT_NULL);
    1585             :         fill_note(note, "CORE", NT_AUXV, i * sizeof(elf_addr_t), auxv);
    1586             : }
    1587             : 
    1588             : static void fill_siginfo_note(struct memelfnote *note, user_siginfo_t *csigdata,
    1589             :                 const kernel_siginfo_t *siginfo)
    1590             : {
    1591             :         copy_siginfo_to_external(csigdata, siginfo);
    1592             :         fill_note(note, "CORE", NT_SIGINFO, sizeof(*csigdata), csigdata);
    1593             : }
    1594             : 
    1595             : #define MAX_FILE_NOTE_SIZE (4*1024*1024)
    1596             : /*
    1597             :  * Format of NT_FILE note:
    1598             :  *
    1599             :  * long count     -- how many files are mapped
    1600             :  * long page_size -- units for file_ofs
    1601             :  * array of [COUNT] elements of
    1602             :  *   long start
    1603             :  *   long end
    1604             :  *   long file_ofs
    1605             :  * followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...
    1606             :  */
    1607             : static int fill_files_note(struct memelfnote *note)
    1608             : {
    1609             :         struct mm_struct *mm = current->mm;
    1610             :         struct vm_area_struct *vma;
    1611             :         unsigned count, size, names_ofs, remaining, n;
    1612             :         user_long_t *data;
    1613             :         user_long_t *start_end_ofs;
    1614             :         char *name_base, *name_curpos;
    1615             : 
    1616             :         /* *Estimated* file count and total data size needed */
    1617             :         count = mm->map_count;
    1618             :         if (count > UINT_MAX / 64)
    1619             :                 return -EINVAL;
    1620             :         size = count * 64;
    1621             : 
    1622             :         names_ofs = (2 + 3 * count) * sizeof(data[0]);
    1623             :  alloc:
    1624             :         if (size >= MAX_FILE_NOTE_SIZE) /* paranoia check */
    1625             :                 return -EINVAL;
    1626             :         size = round_up(size, PAGE_SIZE);
    1627             :         /*
    1628             :          * "size" can be 0 here legitimately.
    1629             :          * Let it ENOMEM and omit NT_FILE section which will be empty anyway.
    1630             :          */
    1631             :         data = kvmalloc(size, GFP_KERNEL);
    1632             :         if (ZERO_OR_NULL_PTR(data))
    1633             :                 return -ENOMEM;
    1634             : 
    1635             :         start_end_ofs = data + 2;
    1636             :         name_base = name_curpos = ((char *)data) + names_ofs;
    1637             :         remaining = size - names_ofs;
    1638             :         count = 0;
    1639             :         for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) {
    1640             :                 struct file *file;
    1641             :                 const char *filename;
    1642             : 
    1643             :                 file = vma->vm_file;
    1644             :                 if (!file)
    1645             :                         continue;
    1646             :                 filename = file_path(file, name_curpos, remaining);
    1647             :                 if (IS_ERR(filename)) {
    1648             :                         if (PTR_ERR(filename) == -ENAMETOOLONG) {
    1649             :                                 kvfree(data);
    1650             :                                 size = size * 5 / 4;
    1651             :                                 goto alloc;
    1652             :                         }
    1653             :                         continue;
    1654             :                 }
    1655             : 
    1656             :                 /* file_path() fills at the end, move name down */
    1657             :                 /* n = strlen(filename) + 1: */
    1658             :                 n = (name_curpos + remaining) - filename;
    1659             :                 remaining = filename - name_curpos;
    1660             :                 memmove(name_curpos, filename, n);
    1661             :                 name_curpos += n;
    1662             : 
    1663             :                 *start_end_ofs++ = vma->vm_start;
    1664             :                 *start_end_ofs++ = vma->vm_end;
    1665             :                 *start_end_ofs++ = vma->vm_pgoff;
    1666             :                 count++;
    1667             :         }
    1668             : 
    1669             :         /* Now we know exact count of files, can store it */
    1670             :         data[0] = count;
    1671             :         data[1] = PAGE_SIZE;
    1672             :         /*
    1673             :          * Count usually is less than mm->map_count,
    1674             :          * we need to move filenames down.
    1675             :          */
    1676             :         n = mm->map_count - count;
    1677             :         if (n != 0) {
    1678             :                 unsigned shift_bytes = n * 3 * sizeof(data[0]);
    1679             :                 memmove(name_base - shift_bytes, name_base,
    1680             :                         name_curpos - name_base);
    1681             :                 name_curpos -= shift_bytes;
    1682             :         }
    1683             : 
    1684             :         size = name_curpos - (char *)data;
    1685             :         fill_note(note, "CORE", NT_FILE, size, data);
    1686             :         return 0;
    1687             : }
    1688             : 
    1689             : #ifdef CORE_DUMP_USE_REGSET
    1690             : #include <linux/regset.h>
    1691             : 
    1692             : struct elf_thread_core_info {
    1693             :         struct elf_thread_core_info *next;
    1694             :         struct task_struct *task;
    1695             :         struct elf_prstatus prstatus;
    1696             :         struct memelfnote notes[];
    1697             : };
    1698             : 
    1699             : struct elf_note_info {
    1700             :         struct elf_thread_core_info *thread;
    1701             :         struct memelfnote psinfo;
    1702             :         struct memelfnote signote;
    1703             :         struct memelfnote auxv;
    1704             :         struct memelfnote files;
    1705             :         user_siginfo_t csigdata;
    1706             :         size_t size;
    1707             :         int thread_notes;
    1708             : };
    1709             : 
    1710             : /*
    1711             :  * When a regset has a writeback hook, we call it on each thread before
    1712             :  * dumping user memory.  On register window machines, this makes sure the
    1713             :  * user memory backing the register data is up to date before we read it.
    1714             :  */
    1715             : static void do_thread_regset_writeback(struct task_struct *task,
    1716             :                                        const struct user_regset *regset)
    1717             : {
    1718             :         if (regset->writeback)
    1719             :                 regset->writeback(task, regset, 1);
    1720             : }
    1721             : 
    1722             : #ifndef PRSTATUS_SIZE
    1723             : #define PRSTATUS_SIZE sizeof(struct elf_prstatus)
    1724             : #endif
    1725             : 
    1726             : #ifndef SET_PR_FPVALID
    1727             : #define SET_PR_FPVALID(S) ((S)->pr_fpvalid = 1)
    1728             : #endif
    1729             : 
    1730             : static int fill_thread_core_info(struct elf_thread_core_info *t,
    1731             :                                  const struct user_regset_view *view,
    1732             :                                  long signr, size_t *total)
    1733             : {
    1734             :         unsigned int i;
    1735             : 
    1736             :         /*
    1737             :          * NT_PRSTATUS is the one special case, because the regset data
    1738             :          * goes into the pr_reg field inside the note contents, rather
    1739             :          * than being the whole note contents.  We fill the reset in here.
    1740             :          * We assume that regset 0 is NT_PRSTATUS.
    1741             :          */
    1742             :         fill_prstatus(&t->prstatus.common, t->task, signr);
    1743             :         regset_get(t->task, &view->regsets[0],
    1744             :                    sizeof(t->prstatus.pr_reg), &t->prstatus.pr_reg);
    1745             : 
    1746             :         fill_note(&t->notes[0], "CORE", NT_PRSTATUS,
    1747             :                   PRSTATUS_SIZE, &t->prstatus);
    1748             :         *total += notesize(&t->notes[0]);
    1749             : 
    1750             :         do_thread_regset_writeback(t->task, &view->regsets[0]);
    1751             : 
    1752             :         /*
    1753             :          * Each other regset might generate a note too.  For each regset
    1754             :          * that has no core_note_type or is inactive, we leave t->notes[i]
    1755             :          * all zero and we'll know to skip writing it later.
    1756             :          */
    1757             :         for (i = 1; i < view->n; ++i) {
    1758             :                 const struct user_regset *regset = &view->regsets[i];
    1759             :                 int note_type = regset->core_note_type;
    1760             :                 bool is_fpreg = note_type == NT_PRFPREG;
    1761             :                 void *data;
    1762             :                 int ret;
    1763             : 
    1764             :                 do_thread_regset_writeback(t->task, regset);
    1765             :                 if (!note_type) // not for coredumps
    1766             :                         continue;
    1767             :                 if (regset->active && regset->active(t->task, regset) <= 0)
    1768             :                         continue;
    1769             : 
    1770             :                 ret = regset_get_alloc(t->task, regset, ~0U, &data);
    1771             :                 if (ret < 0)
    1772             :                         continue;
    1773             : 
    1774             :                 if (is_fpreg)
    1775             :                         SET_PR_FPVALID(&t->prstatus);
    1776             : 
    1777             :                 fill_note(&t->notes[i], is_fpreg ? "CORE" : "LINUX",
    1778             :                           note_type, ret, data);
    1779             : 
    1780             :                 *total += notesize(&t->notes[i]);
    1781             :         }
    1782             : 
    1783             :         return 1;
    1784             : }
    1785             : 
    1786             : static int fill_note_info(struct elfhdr *elf, int phdrs,
    1787             :                           struct elf_note_info *info,
    1788             :                           const kernel_siginfo_t *siginfo, struct pt_regs *regs)
    1789             : {
    1790             :         struct task_struct *dump_task = current;
    1791             :         const struct user_regset_view *view = task_user_regset_view(dump_task);
    1792             :         struct elf_thread_core_info *t;
    1793             :         struct elf_prpsinfo *psinfo;
    1794             :         struct core_thread *ct;
    1795             :         unsigned int i;
    1796             : 
    1797             :         info->size = 0;
    1798             :         info->thread = NULL;
    1799             : 
    1800             :         psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
    1801             :         if (psinfo == NULL) {
    1802             :                 info->psinfo.data = NULL; /* So we don't free this wrongly */
    1803             :                 return 0;
    1804             :         }
    1805             : 
    1806             :         fill_note(&info->psinfo, "CORE", NT_PRPSINFO, sizeof(*psinfo), psinfo);
    1807             : 
    1808             :         /*
    1809             :          * Figure out how many notes we're going to need for each thread.
    1810             :          */
    1811             :         info->thread_notes = 0;
    1812             :         for (i = 0; i < view->n; ++i)
    1813             :                 if (view->regsets[i].core_note_type != 0)
    1814             :                         ++info->thread_notes;
    1815             : 
    1816             :         /*
    1817             :          * Sanity check.  We rely on regset 0 being in NT_PRSTATUS,
    1818             :          * since it is our one special case.
    1819             :          */
    1820             :         if (unlikely(info->thread_notes == 0) ||
    1821             :             unlikely(view->regsets[0].core_note_type != NT_PRSTATUS)) {
    1822             :                 WARN_ON(1);
    1823             :                 return 0;
    1824             :         }
    1825             : 
    1826             :         /*
    1827             :          * Initialize the ELF file header.
    1828             :          */
    1829             :         fill_elf_header(elf, phdrs,
    1830             :                         view->e_machine, view->e_flags);
    1831             : 
    1832             :         /*
    1833             :          * Allocate a structure for each thread.
    1834             :          */
    1835             :         for (ct = &dump_task->mm->core_state->dumper; ct; ct = ct->next) {
    1836             :                 t = kzalloc(offsetof(struct elf_thread_core_info,
    1837             :                                      notes[info->thread_notes]),
    1838             :                             GFP_KERNEL);
    1839             :                 if (unlikely(!t))
    1840             :                         return 0;
    1841             : 
    1842             :                 t->task = ct->task;
    1843             :                 if (ct->task == dump_task || !info->thread) {
    1844             :                         t->next = info->thread;
    1845             :                         info->thread = t;
    1846             :                 } else {
    1847             :                         /*
    1848             :                          * Make sure to keep the original task at
    1849             :                          * the head of the list.
    1850             :                          */
    1851             :                         t->next = info->thread->next;
    1852             :                         info->thread->next = t;
    1853             :                 }
    1854             :         }
    1855             : 
    1856             :         /*
    1857             :          * Now fill in each thread's information.
    1858             :          */
    1859             :         for (t = info->thread; t != NULL; t = t->next)
    1860             :                 if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size))
    1861             :                         return 0;
    1862             : 
    1863             :         /*
    1864             :          * Fill in the two process-wide notes.
    1865             :          */
    1866             :         fill_psinfo(psinfo, dump_task->group_leader, dump_task->mm);
    1867             :         info->size += notesize(&info->psinfo);
    1868             : 
    1869             :         fill_siginfo_note(&info->signote, &info->csigdata, siginfo);
    1870             :         info->size += notesize(&info->signote);
    1871             : 
    1872             :         fill_auxv_note(&info->auxv, current->mm);
    1873             :         info->size += notesize(&info->auxv);
    1874             : 
    1875             :         if (fill_files_note(&info->files) == 0)
    1876             :                 info->size += notesize(&info->files);
    1877             : 
    1878             :         return 1;
    1879             : }
    1880             : 
    1881             : static size_t get_note_info_size(struct elf_note_info *info)
    1882             : {
    1883             :         return info->size;
    1884             : }
    1885             : 
    1886             : /*
    1887             :  * Write all the notes for each thread.  When writing the first thread, the
    1888             :  * process-wide notes are interleaved after the first thread-specific note.
    1889             :  */
    1890             : static int write_note_info(struct elf_note_info *info,
    1891             :                            struct coredump_params *cprm)
    1892             : {
    1893             :         bool first = true;
    1894             :         struct elf_thread_core_info *t = info->thread;
    1895             : 
    1896             :         do {
    1897             :                 int i;
    1898             : 
    1899             :                 if (!writenote(&t->notes[0], cprm))
    1900             :                         return 0;
    1901             : 
    1902             :                 if (first && !writenote(&info->psinfo, cprm))
    1903             :                         return 0;
    1904             :                 if (first && !writenote(&info->signote, cprm))
    1905             :                         return 0;
    1906             :                 if (first && !writenote(&info->auxv, cprm))
    1907             :                         return 0;
    1908             :                 if (first && info->files.data &&
    1909             :                                 !writenote(&info->files, cprm))
    1910             :                         return 0;
    1911             : 
    1912             :                 for (i = 1; i < info->thread_notes; ++i)
    1913             :                         if (t->notes[i].data &&
    1914             :                             !writenote(&t->notes[i], cprm))
    1915             :                                 return 0;
    1916             : 
    1917             :                 first = false;
    1918             :                 t = t->next;
    1919             :         } while (t);
    1920             : 
    1921             :         return 1;
    1922             : }
    1923             : 
    1924             : static void free_note_info(struct elf_note_info *info)
    1925             : {
    1926             :         struct elf_thread_core_info *threads = info->thread;
    1927             :         while (threads) {
    1928             :                 unsigned int i;
    1929             :                 struct elf_thread_core_info *t = threads;
    1930             :                 threads = t->next;
    1931             :                 WARN_ON(t->notes[0].data && t->notes[0].data != &t->prstatus);
    1932             :                 for (i = 1; i < info->thread_notes; ++i)
    1933             :                         kfree(t->notes[i].data);
    1934             :                 kfree(t);
    1935             :         }
    1936             :         kfree(info->psinfo.data);
    1937             :         kvfree(info->files.data);
    1938             : }
    1939             : 
    1940             : #else
    1941             : 
    1942             : /* Here is the structure in which status of each thread is captured. */
    1943             : struct elf_thread_status
    1944             : {
    1945             :         struct list_head list;
    1946             :         struct elf_prstatus prstatus;   /* NT_PRSTATUS */
    1947             :         elf_fpregset_t fpu;             /* NT_PRFPREG */
    1948             :         struct task_struct *thread;
    1949             :         struct memelfnote notes[3];
    1950             :         int num_notes;
    1951             : };
    1952             : 
    1953             : /*
    1954             :  * In order to add the specific thread information for the elf file format,
    1955             :  * we need to keep a linked list of every threads pr_status and then create
    1956             :  * a single section for them in the final core file.
    1957             :  */
    1958             : static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
    1959             : {
    1960             :         int sz = 0;
    1961             :         struct task_struct *p = t->thread;
    1962             :         t->num_notes = 0;
    1963             : 
    1964             :         fill_prstatus(&t->prstatus.common, p, signr);
    1965             :         elf_core_copy_task_regs(p, &t->prstatus.pr_reg); 
    1966             :         
    1967             :         fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus),
    1968             :                   &(t->prstatus));
    1969             :         t->num_notes++;
    1970             :         sz += notesize(&t->notes[0]);
    1971             : 
    1972             :         if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, NULL,
    1973             :                                                                 &t->fpu))) {
    1974             :                 fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu),
    1975             :                           &(t->fpu));
    1976             :                 t->num_notes++;
    1977             :                 sz += notesize(&t->notes[1]);
    1978             :         }
    1979             :         return sz;
    1980             : }
    1981             : 
    1982             : struct elf_note_info {
    1983             :         struct memelfnote *notes;
    1984             :         struct memelfnote *notes_files;
    1985             :         struct elf_prstatus *prstatus;  /* NT_PRSTATUS */
    1986             :         struct elf_prpsinfo *psinfo;    /* NT_PRPSINFO */
    1987             :         struct list_head thread_list;
    1988             :         elf_fpregset_t *fpu;
    1989             :         user_siginfo_t csigdata;
    1990             :         int thread_status_size;
    1991             :         int numnote;
    1992             : };
    1993             : 
    1994             : static int elf_note_info_init(struct elf_note_info *info)
    1995             : {
    1996             :         memset(info, 0, sizeof(*info));
    1997             :         INIT_LIST_HEAD(&info->thread_list);
    1998             : 
    1999             :         /* Allocate space for ELF notes */
    2000             :         info->notes = kmalloc_array(8, sizeof(struct memelfnote), GFP_KERNEL);
    2001             :         if (!info->notes)
    2002             :                 return 0;
    2003             :         info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
    2004             :         if (!info->psinfo)
    2005             :                 return 0;
    2006             :         info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
    2007             :         if (!info->prstatus)
    2008             :                 return 0;
    2009             :         info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
    2010             :         if (!info->fpu)
    2011             :                 return 0;
    2012             :         return 1;
    2013             : }
    2014             : 
    2015             : static int fill_note_info(struct elfhdr *elf, int phdrs,
    2016             :                           struct elf_note_info *info,
    2017             :                           const kernel_siginfo_t *siginfo, struct pt_regs *regs)
    2018             : {
    2019             :         struct core_thread *ct;
    2020             :         struct elf_thread_status *ets;
    2021             : 
    2022             :         if (!elf_note_info_init(info))
    2023             :                 return 0;
    2024             : 
    2025             :         for (ct = current->mm->core_state->dumper.next;
    2026             :                                         ct; ct = ct->next) {
    2027             :                 ets = kzalloc(sizeof(*ets), GFP_KERNEL);
    2028             :                 if (!ets)
    2029             :                         return 0;
    2030             : 
    2031             :                 ets->thread = ct->task;
    2032             :                 list_add(&ets->list, &info->thread_list);
    2033             :         }
    2034             : 
    2035             :         list_for_each_entry(ets, &info->thread_list, list) {
    2036             :                 int sz;
    2037             : 
    2038             :                 sz = elf_dump_thread_status(siginfo->si_signo, ets);
    2039             :                 info->thread_status_size += sz;
    2040             :         }
    2041             :         /* now collect the dump for the current */
    2042             :         memset(info->prstatus, 0, sizeof(*info->prstatus));
    2043             :         fill_prstatus(&info->prstatus->common, current, siginfo->si_signo);
    2044             :         elf_core_copy_regs(&info->prstatus->pr_reg, regs);
    2045             : 
    2046             :         /* Set up header */
    2047             :         fill_elf_header(elf, phdrs, ELF_ARCH, ELF_CORE_EFLAGS);
    2048             : 
    2049             :         /*
    2050             :          * Set up the notes in similar form to SVR4 core dumps made
    2051             :          * with info from their /proc.
    2052             :          */
    2053             : 
    2054             :         fill_note(info->notes + 0, "CORE", NT_PRSTATUS,
    2055             :                   sizeof(*info->prstatus), info->prstatus);
    2056             :         fill_psinfo(info->psinfo, current->group_leader, current->mm);
    2057             :         fill_note(info->notes + 1, "CORE", NT_PRPSINFO,
    2058             :                   sizeof(*info->psinfo), info->psinfo);
    2059             : 
    2060             :         fill_siginfo_note(info->notes + 2, &info->csigdata, siginfo);
    2061             :         fill_auxv_note(info->notes + 3, current->mm);
    2062             :         info->numnote = 4;
    2063             : 
    2064             :         if (fill_files_note(info->notes + info->numnote) == 0) {
    2065             :                 info->notes_files = info->notes + info->numnote;
    2066             :                 info->numnote++;
    2067             :         }
    2068             : 
    2069             :         /* Try to dump the FPU. */
    2070             :         info->prstatus->pr_fpvalid = elf_core_copy_task_fpregs(current, regs,
    2071             :                                                                info->fpu);
    2072             :         if (info->prstatus->pr_fpvalid)
    2073             :                 fill_note(info->notes + info->numnote++,
    2074             :                           "CORE", NT_PRFPREG, sizeof(*info->fpu), info->fpu);
    2075             :         return 1;
    2076             : }
    2077             : 
    2078             : static size_t get_note_info_size(struct elf_note_info *info)
    2079             : {
    2080             :         int sz = 0;
    2081             :         int i;
    2082             : 
    2083             :         for (i = 0; i < info->numnote; i++)
    2084             :                 sz += notesize(info->notes + i);
    2085             : 
    2086             :         sz += info->thread_status_size;
    2087             : 
    2088             :         return sz;
    2089             : }
    2090             : 
    2091             : static int write_note_info(struct elf_note_info *info,
    2092             :                            struct coredump_params *cprm)
    2093             : {
    2094             :         struct elf_thread_status *ets;
    2095             :         int i;
    2096             : 
    2097             :         for (i = 0; i < info->numnote; i++)
    2098             :                 if (!writenote(info->notes + i, cprm))
    2099             :                         return 0;
    2100             : 
    2101             :         /* write out the thread status notes section */
    2102             :         list_for_each_entry(ets, &info->thread_list, list) {
    2103             :                 for (i = 0; i < ets->num_notes; i++)
    2104             :                         if (!writenote(&ets->notes[i], cprm))
    2105             :                                 return 0;
    2106             :         }
    2107             : 
    2108             :         return 1;
    2109             : }
    2110             : 
    2111             : static void free_note_info(struct elf_note_info *info)
    2112             : {
    2113             :         while (!list_empty(&info->thread_list)) {
    2114             :                 struct list_head *tmp = info->thread_list.next;
    2115             :                 list_del(tmp);
    2116             :                 kfree(list_entry(tmp, struct elf_thread_status, list));
    2117             :         }
    2118             : 
    2119             :         /* Free data possibly allocated by fill_files_note(): */
    2120             :         if (info->notes_files)
    2121             :                 kvfree(info->notes_files->data);
    2122             : 
    2123             :         kfree(info->prstatus);
    2124             :         kfree(info->psinfo);
    2125             :         kfree(info->notes);
    2126             :         kfree(info->fpu);
    2127             : }
    2128             : 
    2129             : #endif
    2130             : 
    2131             : static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
    2132             :                              elf_addr_t e_shoff, int segs)
    2133             : {
    2134             :         elf->e_shoff = e_shoff;
    2135             :         elf->e_shentsize = sizeof(*shdr4extnum);
    2136             :         elf->e_shnum = 1;
    2137             :         elf->e_shstrndx = SHN_UNDEF;
    2138             : 
    2139             :         memset(shdr4extnum, 0, sizeof(*shdr4extnum));
    2140             : 
    2141             :         shdr4extnum->sh_type = SHT_NULL;
    2142             :         shdr4extnum->sh_size = elf->e_shnum;
    2143             :         shdr4extnum->sh_link = elf->e_shstrndx;
    2144             :         shdr4extnum->sh_info = segs;
    2145             : }
    2146             : 
    2147             : /*
    2148             :  * Actual dumper
    2149             :  *
    2150             :  * This is a two-pass process; first we find the offsets of the bits,
    2151             :  * and then they are actually written out.  If we run out of core limit
    2152             :  * we just truncate.
    2153             :  */
    2154             : static int elf_core_dump(struct coredump_params *cprm)
    2155             : {
    2156             :         int has_dumped = 0;
    2157             :         int vma_count, segs, i;
    2158             :         size_t vma_data_size;
    2159             :         struct elfhdr elf;
    2160             :         loff_t offset = 0, dataoff;
    2161             :         struct elf_note_info info = { };
    2162             :         struct elf_phdr *phdr4note = NULL;
    2163             :         struct elf_shdr *shdr4extnum = NULL;
    2164             :         Elf_Half e_phnum;
    2165             :         elf_addr_t e_shoff;
    2166             :         struct core_vma_metadata *vma_meta;
    2167             : 
    2168             :         if (dump_vma_snapshot(cprm, &vma_count, &vma_meta, &vma_data_size))
    2169             :                 return 0;
    2170             : 
    2171             :         /*
    2172             :          * The number of segs are recored into ELF header as 16bit value.
    2173             :          * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here.
    2174             :          */
    2175             :         segs = vma_count + elf_core_extra_phdrs();
    2176             : 
    2177             :         /* for notes section */
    2178             :         segs++;
    2179             : 
    2180             :         /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
    2181             :          * this, kernel supports extended numbering. Have a look at
    2182             :          * include/linux/elf.h for further information. */
    2183             :         e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
    2184             : 
    2185             :         /*
    2186             :          * Collect all the non-memory information about the process for the
    2187             :          * notes.  This also sets up the file header.
    2188             :          */
    2189             :         if (!fill_note_info(&elf, e_phnum, &info, cprm->siginfo, cprm->regs))
    2190             :                 goto end_coredump;
    2191             : 
    2192             :         has_dumped = 1;
    2193             : 
    2194             :         offset += sizeof(elf);                          /* Elf header */
    2195             :         offset += segs * sizeof(struct elf_phdr);       /* Program headers */
    2196             : 
    2197             :         /* Write notes phdr entry */
    2198             :         {
    2199             :                 size_t sz = get_note_info_size(&info);
    2200             : 
    2201             :                 /* For cell spufs */
    2202             :                 sz += elf_coredump_extra_notes_size();
    2203             : 
    2204             :                 phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
    2205             :                 if (!phdr4note)
    2206             :                         goto end_coredump;
    2207             : 
    2208             :                 fill_elf_note_phdr(phdr4note, sz, offset);
    2209             :                 offset += sz;
    2210             :         }
    2211             : 
    2212             :         dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
    2213             : 
    2214             :         offset += vma_data_size;
    2215             :         offset += elf_core_extra_data_size();
    2216             :         e_shoff = offset;
    2217             : 
    2218             :         if (e_phnum == PN_XNUM) {
    2219             :                 shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
    2220             :                 if (!shdr4extnum)
    2221             :                         goto end_coredump;
    2222             :                 fill_extnum_info(&elf, shdr4extnum, e_shoff, segs);
    2223             :         }
    2224             : 
    2225             :         offset = dataoff;
    2226             : 
    2227             :         if (!dump_emit(cprm, &elf, sizeof(elf)))
    2228             :                 goto end_coredump;
    2229             : 
    2230             :         if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note)))
    2231             :                 goto end_coredump;
    2232             : 
    2233             :         /* Write program headers for segments dump */
    2234             :         for (i = 0; i < vma_count; i++) {
    2235             :                 struct core_vma_metadata *meta = vma_meta + i;
    2236             :                 struct elf_phdr phdr;
    2237             : 
    2238             :                 phdr.p_type = PT_LOAD;
    2239             :                 phdr.p_offset = offset;
    2240             :                 phdr.p_vaddr = meta->start;
    2241             :                 phdr.p_paddr = 0;
    2242             :                 phdr.p_filesz = meta->dump_size;
    2243             :                 phdr.p_memsz = meta->end - meta->start;
    2244             :                 offset += phdr.p_filesz;
    2245             :                 phdr.p_flags = 0;
    2246             :                 if (meta->flags & VM_READ)
    2247             :                         phdr.p_flags |= PF_R;
    2248             :                 if (meta->flags & VM_WRITE)
    2249             :                         phdr.p_flags |= PF_W;
    2250             :                 if (meta->flags & VM_EXEC)
    2251             :                         phdr.p_flags |= PF_X;
    2252             :                 phdr.p_align = ELF_EXEC_PAGESIZE;
    2253             : 
    2254             :                 if (!dump_emit(cprm, &phdr, sizeof(phdr)))
    2255             :                         goto end_coredump;
    2256             :         }
    2257             : 
    2258             :         if (!elf_core_write_extra_phdrs(cprm, offset))
    2259             :                 goto end_coredump;
    2260             : 
    2261             :         /* write out the notes section */
    2262             :         if (!write_note_info(&info, cprm))
    2263             :                 goto end_coredump;
    2264             : 
    2265             :         /* For cell spufs */
    2266             :         if (elf_coredump_extra_notes_write(cprm))
    2267             :                 goto end_coredump;
    2268             : 
    2269             :         /* Align to page */
    2270             :         if (!dump_skip(cprm, dataoff - cprm->pos))
    2271             :                 goto end_coredump;
    2272             : 
    2273             :         for (i = 0; i < vma_count; i++) {
    2274             :                 struct core_vma_metadata *meta = vma_meta + i;
    2275             : 
    2276             :                 if (!dump_user_range(cprm, meta->start, meta->dump_size))
    2277             :                         goto end_coredump;
    2278             :         }
    2279             :         dump_truncate(cprm);
    2280             : 
    2281             :         if (!elf_core_write_extra_data(cprm))
    2282             :                 goto end_coredump;
    2283             : 
    2284             :         if (e_phnum == PN_XNUM) {
    2285             :                 if (!dump_emit(cprm, shdr4extnum, sizeof(*shdr4extnum)))
    2286             :                         goto end_coredump;
    2287             :         }
    2288             : 
    2289             : end_coredump:
    2290             :         free_note_info(&info);
    2291             :         kfree(shdr4extnum);
    2292             :         kvfree(vma_meta);
    2293             :         kfree(phdr4note);
    2294             :         return has_dumped;
    2295             : }
    2296             : 
    2297             : #endif          /* CONFIG_ELF_CORE */
    2298             : 
    2299           2 : static int __init init_elf_binfmt(void)
    2300             : {
    2301           2 :         register_binfmt(&elf_format);
    2302           2 :         return 0;
    2303             : }
    2304             : 
    2305           0 : static void __exit exit_elf_binfmt(void)
    2306             : {
    2307             :         /* Remove the COFF and ELF loaders. */
    2308           0 :         unregister_binfmt(&elf_format);
    2309           0 : }
    2310             : 
    2311             : core_initcall(init_elf_binfmt);
    2312             : module_exit(exit_elf_binfmt);
    2313             : MODULE_LICENSE("GPL");

Generated by: LCOV version 1.14