aboutsummaryrefslogtreecommitdiff
path: root/fs/binfmt_elf_fdpic.c
diff options
context:
space:
mode:
authorMasami Hiramatsu <mhiramat@redhat.com>2010-03-05 13:44:12 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2010-03-06 11:26:46 -0800
commit30736a4d43f4af7f1a7836d6a266be17082195c4 (patch)
tree54e388cdaf4795bdb7651be03c50bba67eb0b43a /fs/binfmt_elf_fdpic.c
parent8d9032bbe4671dc481261ccd4e161cd96e54b118 (diff)
downloadlinux-linaro-stable-30736a4d43f4af7f1a7836d6a266be17082195c4.tar.gz
coredump: pass mm->flags as a coredump parameter for consistency
Pass mm->flags as a coredump parameter for consistency. --- 1787 if (mm->core_state || !get_dumpable(mm)) { <- (1) 1788 up_write(&mm->mmap_sem); 1789 put_cred(cred); 1790 goto fail; 1791 } 1792 [...] 1798 if (get_dumpable(mm) == 2) { /* Setuid core dump mode */ <-(2) 1799 flag = O_EXCL; /* Stop rewrite attacks */ 1800 cred->fsuid = 0; /* Dump root private */ 1801 } --- Since dumpable bits are not protected by lock, there is a chance to change these bits between (1) and (2). To solve this issue, this patch copies mm->flags to coredump_params.mm_flags at the beginning of do_coredump() and uses it instead of get_dumpable() while dumping core. This copy is also passed to binfmt->core_dump, since elf*_core_dump() uses dump_filter bits in mm->flags. [akpm@linux-foundation.org: fix merge] Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/binfmt_elf_fdpic.c')
-rw-r--r--fs/binfmt_elf_fdpic.c14
1 files changed, 3 insertions, 11 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index e49d9c06a4b6..6d6a16c5e9bb 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1626,7 +1626,6 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
#endif
int thread_status_size = 0;
elf_addr_t *auxv;
- unsigned long mm_flags;
struct elf_phdr *phdr4note = NULL;
struct elf_shdr *shdr4extnum = NULL;
Elf_Half e_phnum;
@@ -1769,14 +1768,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
/* Page-align dumped data */
dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
- /*
- * We must use the same mm->flags while dumping core to avoid
- * inconsistency between the program headers and bodies, otherwise an
- * unusable core file can be generated.
- */
- mm_flags = current->mm->flags;
-
- offset += elf_core_vma_data_size(mm_flags);
+ offset += elf_core_vma_data_size(cprm->mm_flags);
offset += elf_core_extra_data_size();
e_shoff = offset;
@@ -1809,7 +1801,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
phdr.p_offset = offset;
phdr.p_vaddr = vma->vm_start;
phdr.p_paddr = 0;
- phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0;
+ phdr.p_filesz = maydump(vma, cprm->mm_flags) ? sz : 0;
phdr.p_memsz = sz;
offset += phdr.p_filesz;
phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
@@ -1847,7 +1839,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
goto end_coredump;
if (elf_fdpic_dump_segments(cprm->file, &size, &cprm->limit,
- mm_flags) < 0)
+ cprm->mm_flags) < 0)
goto end_coredump;
if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))