[PATCH 5.4 167/388] ext4: mark block bitmap corrupted when found instead of BUGON

From: Greg Kroah-Hartman
Date: Tue Sep 29 2020 - 08:06:34 EST


From: Dmitry Monakhov <dmonakhov@xxxxxxxxx>

[ Upstream commit eb5760863fc28feab28b567ddcda7e667e638da0 ]

We already has similar code in ext4_mb_complex_scan_group(), but
ext4_mb_simple_scan_group() still affected.

Other reports: https://www.spinics.net/lists/linux-ext4/msg60231.html

Reviewed-by: Andreas Dilger <adilger@xxxxxxxxx>
Signed-off-by: Dmitry Monakhov <dmonakhov@xxxxxxxxx>
Link: https://lore.kernel.org/r/20200310150156.641-1-dmonakhov@xxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ext4/mballoc.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index e1782b2e2e2dd..e5d43d2ee474d 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1901,8 +1901,15 @@ void ext4_mb_simple_scan_group(struct ext4_allocation_context *ac,
BUG_ON(buddy == NULL);

k = mb_find_next_zero_bit(buddy, max, 0);
- BUG_ON(k >= max);
-
+ if (k >= max) {
+ ext4_grp_locked_error(ac->ac_sb, e4b->bd_group, 0, 0,
+ "%d free clusters of order %d. But found 0",
+ grp->bb_counters[i], i);
+ ext4_mark_group_bitmap_corrupted(ac->ac_sb,
+ e4b->bd_group,
+ EXT4_GROUP_INFO_BBITMAP_CORRUPT);
+ break;
+ }
ac->ac_found++;

ac->ac_b_ex.fe_len = 1 << i;
--
2.25.1