diff options
| author | Pan Bian <bianpan2016@163.com> | 2018-11-25 08:58:02 +0800 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2019-02-11 17:54:14 +0000 |
| commit | 2ada5a08b091d1d825c41d61decb6e6db3de3d54 (patch) | |
| tree | 9415cd08608e6958a9c86d1405df675be93c9aba /fs | |
| parent | 8dc4dd2c7b7284a172fc1dd5880fca5d0decbbf2 (diff) | |
ext2: fix potential use after free
commit ecebf55d27a11538ea84aee0be643dd953f830d5 upstream.
The function ext2_xattr_set calls brelse(bh) to drop the reference count
of bh. After that, bh may be freed. However, following brelse(bh),
it reads bh->b_data via macro HDR(bh). This may result in a
use-after-free bug. This patch moves brelse(bh) after reading field.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext2/xattr.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c index 91426141c33a..d5d6ec134d5c 100644 --- a/fs/ext2/xattr.c +++ b/fs/ext2/xattr.c @@ -606,9 +606,9 @@ skip_replace: } cleanup: - brelse(bh); if (!(bh && header == HDR(bh))) kfree(header); + brelse(bh); up_write(&EXT2_I(inode)->xattr_sem); return error; |