diff options
| author | Chandan Rajendra <chandan@linux.vnet.ibm.com> | 2016-11-14 21:26:26 -0500 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-05-29 03:52:16 +0200 |
| commit | 5058951c3ba7cec7df74ddec44c7281ae6ee136f (patch) | |
| tree | 898503110e2d9ce4aee8fe13724c6a58147cd2c6 /fs | |
| parent | a2ffd151c746e5c8d72a046ce8ce5f2368ba1416 (diff) | |
ext4: fix stack memory corruption with 64k block size
[ Upstream commit 30a9d7afe70ed6bd9191d3000e2ef1a34fb58493 ]
The number of 'counters' elements needed in 'struct sg' is
super_block->s_blocksize_bits + 2. Presently we have 16 'counters'
elements in the array. This is insufficient for block sizes >= 32k. In
such cases the memcpy operation performed in ext4_mb_seq_groups_show()
would cause stack memory corruption.
Fixes: c9de560ded61f
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/mballoc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 1c4a9556e..e40e8539c 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2254,7 +2254,7 @@ static int ext4_mb_seq_groups_show(struct seq_file *seq, void *v) struct ext4_group_info *grinfo; struct sg { struct ext4_group_info info; - ext4_grpblk_t counters[16]; + ext4_grpblk_t counters[EXT4_MAX_BLOCK_LOG_SIZE + 2]; } sg; group--; |