diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2013-03-11 23:39:59 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-05 10:16:52 -0700 |
| commit | 503f4bdcc078e7abee273a85ce322de81b18a224 (patch) | |
| tree | 30eb5483102eb88ac8e5d9c9ddb84e6437ddd6ba /fs/ext4/resize.c | |
| parent | 7fb54baf47818c2a76999ff907e2cecf25b98218 (diff) | |
ext4: use atomic64_t for the per-flexbg free_clusters count
commit 90ba983f6889e65a3b506b30dc606aa9d1d46cd2 upstream.
A user who was using a 8TB+ file system and with a very large flexbg
size (> 65536) could cause the atomic_t used in the struct flex_groups
to overflow. This was detected by PaX security patchset:
http://forums.grsecurity.net/viewtopic.php?f=3&t=3289&p=12551#p12551
This bug was introduced in commit 9f24e4208f7e, so it's been around
since 2.6.30. :-(
Fix this by using an atomic64_t for struct orlav_stats's
free_clusters.
[Backported for 3.0-stable. Renamed free_clusters back to free_blocks;
fixed a few more atomic_read's of free_blocks left in 3.0.]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Lingzhu Xiang <lxiang@redhat.com>
Reviewed-by: CAI Qian <caiqian@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ext4/resize.c')
| -rw-r--r-- | fs/ext4/resize.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 244100f08fc..d2661aaca32 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -929,8 +929,8 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) sbi->s_log_groups_per_flex) { ext4_group_t flex_group; flex_group = ext4_flex_group(sbi, input->group); - atomic_add(input->free_blocks_count, - &sbi->s_flex_groups[flex_group].free_blocks); + atomic64_add(input->free_blocks_count, + &sbi->s_flex_groups[flex_group].free_blocks); atomic_add(EXT4_INODES_PER_GROUP(sb), &sbi->s_flex_groups[flex_group].free_inodes); } |