diff options
| author | Baokun Li <libaokun1@huawei.com> | 2024-01-04 22:20:38 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-03-01 13:34:50 +0100 |
| commit | 0184747b552d6b5a14db3b7fcc3b792ce64dedd1 (patch) | |
| tree | 9028952b1f4f5fc4c4034d2344c465f0c89cb553 | |
| parent | f32d2a745b02123258026e105a008f474f896d6a (diff) | |
ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()
[ Upstream commit 4530b3660d396a646aad91a787b6ab37cf604b53 ]
Determine if the group block bitmap is corrupted before using ac_b_ex in
ext4_mb_try_best_found() to avoid allocating blocks from a group with a
corrupted block bitmap in the following concurrency and making the
situation worse.
ext4_mb_regular_allocator
ext4_lock_group(sb, group)
ext4_mb_good_group
// check if the group bbitmap is corrupted
ext4_mb_complex_scan_group
// Scan group gets ac_b_ex but doesn't use it
ext4_unlock_group(sb, group)
ext4_mark_group_bitmap_corrupted(group)
// The block bitmap was corrupted during
// the group unlock gap.
ext4_mb_try_best_found
ext4_lock_group(ac->ac_sb, group)
ext4_mb_use_best_found
mb_mark_used
// Allocating blocks in block bitmap corrupted group
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240104142040.2835097-7-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/ext4/mballoc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 9eac63e5a251..bc9630f4c09c 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2304,6 +2304,9 @@ void ext4_mb_try_best_found(struct ext4_allocation_context *ac, return; ext4_lock_group(ac->ac_sb, group); + if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(e4b->bd_info))) + goto out; + max = mb_find_extent(e4b, ex.fe_start, ex.fe_len, &ex); if (max > 0) { @@ -2311,6 +2314,7 @@ void ext4_mb_try_best_found(struct ext4_allocation_context *ac, ext4_mb_use_best_found(ac, e4b); } +out: ext4_unlock_group(ac->ac_sb, group); ext4_mb_unload_buddy(e4b); } |