diff options
author | Oscar Salvador <osalvador@suse.de> | 2018-07-14 02:59:13 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-07-14 21:11:10 +0300 |
commit | 24962af7e1041b7e50c1bc71d8d10dc678c556b5 (patch) | |
tree | bd8ad1a349422c13872dfc60a8c697fd2585590b | |
parent | fa8cbda88db12e632a8987c94b66f5caf25bcec4 (diff) | |
download | linux-24962af7e1041b7e50c1bc71d8d10dc678c556b5.tar.xz |
fs, elf: make sure to page align bss in load_elf_library
The current code does not make sure to page align bss before calling
vm_brk(), and this can lead to a VM_BUG_ON() in __mm_populate() due to
the requested lenght not being correctly aligned.
Let us make sure to align it properly.
Kees: only applicable to CONFIG_USELIB kernels: 32-bit and configured
for libc5.
Link: http://lkml.kernel.org/r/20180705145539.9627-1-osalvador@techadventures.net
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reported-by: syzbot+5dcb560fe12aa5091c06@syzkaller.appspotmail.com
Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | fs/binfmt_elf.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 0ac456b52bdd..816cc921cf36 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1259,9 +1259,8 @@ static int load_elf_library(struct file *file) goto out_free_ph; } - len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr + - ELF_MIN_ALIGN - 1); - bss = eppnt->p_memsz + eppnt->p_vaddr; + len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr); + bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr); if (bss > len) { error = vm_brk(len, bss - len); if (error) |