evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ext2: fix potential use after free

Browse source 
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>
This commit is contained in:
Pan Bian 2018-11-25 08:58:02 +08:00 • committed by Greg Kroah-Hartman
parent 4d5f99ec00
commit 89ed5b72e5
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
fs/ext2/xattr.c
View file

@ -605,9 +605,9 @@ skip_replace:
}
cleanup:
brelse(bh);
if (!(bh && header == HDR(bh)))
kfree(header);
brelse(bh);
up_write(&EXT2_I(inode)->xattr_sem);
return error;