From: Ye Bin <[email protected]>
Syzbot report issue as follows:
EXT4-fs error (device loop0): ext4_validate_block_bitmap:398: comm rep: bg 0: block 5: invalid block bitmap
EXT4-fs (loop0): Delayed block allocation failed for inode 18 at logical offset 0 with max blocks 32 with error 28
EXT4-fs (loop0): This should not happen!! Data will be lost
EXT4-fs (loop0): Total free blocks count 0
EXT4-fs (loop0): Free/Dirty block details
EXT4-fs (loop0): free_blocks=0
EXT4-fs (loop0): dirty_blocks=32
EXT4-fs (loop0): Block reservation details
EXT4-fs (loop0): i_reserved_data_blocks=2
EXT4-fs (loop0): Inode 18 (00000000845cd634): i_reserved_data_blocks (1) not cleared!
Above issue happens as follows:
Assume:
sbi->s_cluster_ratio = 16
Step1: Insert delay block [0, 31] -> ei->i_reserved_data_blocks=2
Step2:
ext4_writepages
mpage_map_and_submit_extent -> return failed
mpage_release_unused_pages -> to release [0, 30]
ext4_es_remove_extent -> remove lblk=0 end=30
__es_remove_extent -> len1=0 len2=31-30=1
__es_remove_extent:
...
if (len2 > 0) {
...
if (len1 > 0) {
...
} else {
es->es_lblk = end + 1;
es->es_len = len2;
...
}
if (count_reserved)
count_rsvd(inode, lblk, orig_es.es_len - len1 - len2, &orig_es, &rc);
goto out; -> will return but didn't calculate 'reserved'
...
Step3: ext4_destroy_inode -> trigger "i_reserved_data_blocks (1) not cleared!"
To solve above issue if 'len2>0' call 'get_rsvd()' before goto out.
Reported-by: [email protected]
Signed-off-by: Ye Bin <[email protected]>
---
fs/ext4/extents_status.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index cd0a861853e3..4684eaea9471 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -1371,7 +1371,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
if (count_reserved)
count_rsvd(inode, lblk, orig_es.es_len - len1 - len2,
&orig_es, &rc);
- goto out;
+ goto count;
}
if (len1 > 0) {
@@ -1413,6 +1413,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
}
}
+count:
if (count_reserved)
*reserved = get_rsvd(inode, end, es, &rc);
out:
--
2.31.1