summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorOscar Salvador <osalvador@suse.de>2018-07-14 02:59:13 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2018-07-14 21:11:10 +0300
commit24962af7e1041b7e50c1bc71d8d10dc678c556b5 (patch)
treebd8ad1a349422c13872dfc60a8c697fd2585590b
parentfa8cbda88db12e632a8987c94b66f5caf25bcec4 (diff)
downloadlinux-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.c5
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)