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| author | Pan Bian <bianpan2016@163.com> | 2018-11-25 08:58:02 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-05 19:41:25 +0100 |
| commit | 086d1f60f874829124ebeaf7d2223a414221ca3b (patch) | |
| tree | bc46ed17d957bf5b9276406c6d9d1f3d5e0e9bbc /fs/ext2/xattr.c | |
| parent | e2ec0cb4d09277730decd5e1a9c75fb18ccb7d7a (diff) | |
| download | linux-rt-086d1f60f874829124ebeaf7d2223a414221ca3b.tar.gz | |
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.
CC: stable@vger.kernel.org
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ext2/xattr.c')
| -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 62d9a659a8ff..dd8f10db82e9 100644 --- a/fs/ext2/xattr.c +++ b/fs/ext2/xattr.c @@ -612,9 +612,9 @@ skip_replace: } cleanup: - brelse(bh); if (!(bh && header == HDR(bh))) kfree(header); + brelse(bh); up_write(&EXT2_I(inode)->xattr_sem); return error; |