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| author | Baokun Li <libaokun1@huawei.com> | 2024-01-04 22:20:38 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-03-01 13:06:09 +0100 |
| commit | 21f8cfe79f776287459343e9cfa6055af61328ea (patch) | |
| tree | 164452c6035ed8625921b730e4a63d8454073e41 | |
| parent | 3f25115864b2abfac4f9267475ed9419073aa560 (diff) | |
| download | linux-stable-21f8cfe79f776287459343e9cfa6055af61328ea.tar.gz linux-stable-21f8cfe79f776287459343e9cfa6055af61328ea.tar.bz2 linux-stable-21f8cfe79f776287459343e9cfa6055af61328ea.zip | |
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 df390979058f..e0dd01cb1a0e 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1802,6 +1802,9 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac, return err; 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) { @@ -1809,6 +1812,7 @@ int 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); |