diff options
| author | Chandan Rajendra <chandan@linux.vnet.ibm.com> | 2016-11-14 21:26:26 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-06 11:16:12 +0100 |
| commit | 7b74c351de1c135faf6f80226dedf3aba697464a (patch) | |
| tree | 3c4defec999c633312e019601020a6d9509bd88a | |
| parent | 26492d8a22b013df435eadd91eeba2c8701206f6 (diff) | |
ext4: fix stack memory corruption with 64k block size
commit 30a9d7afe70ed6bd9191d3000e2ef1a34fb58493 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 748dec05ec7b..b7a3957a9dca 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2287,7 +2287,7 @@ 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--; |