path: root/kernel
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authorRusty Russell <rusty@rustcorp.com.au>2010-08-05 12:59:08 -0600
committerRusty Russell <rusty@rustcorp.com.au>2010-08-05 12:59:08 +0930
commit511ca6ae43fbe0a7c9e0b50ad275f7ef24ef3b58 (patch)
tree596d11de1a99dfce758465de009a97ccdb7da011 /kernel
parenteded41c1c6466081e0eb00d38719c6e6ee81a5d4 (diff)
module: fix crash in get_ksymbol() when oopsing in module init
Andrew had the sole pleasure of tickling this bug in linux-next; when we set up "info->strtab" it's pointing into the temporary copy of the module. For most uses that is fine, but kallsyms keeps a pointer around during module load (inside mod->strtab). If we oops for some reason inside a module's init function, kallsyms will use the mod->strtab pointer into the now-freed temporary module copy. (Later oopses work fine: after init we overwrite mod->strtab to point to a compacted core-only strtab). Reported-by: Andrew "Grumpy" Morton <akpm@linux-foundation.org> Signed-off-by: Rusty "Buggy" Russell <rusty@rustcorp.com.au> Tested-by: Andrew "Happy" Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'kernel')
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 79c4d6f69dd7..60cdd0459eac 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2045,7 +2045,8 @@ static void add_kallsyms(struct module *mod, struct load_info *info,
mod->symtab = (void *)symsec->sh_addr;
mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
- mod->strtab = info->strtab;
+ /* Make sure we get permanent strtab: don't use info->strtab. */
+ mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
/* Set types up while we still have access to sections. */
for (i = 0; i < mod->num_symtab; i++)

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