Fix a bug where nilfs_get_block() returns a successful status when
searching and inserting the specified block both fail inconsistently.
If this inconsistent behavior is not due to a previously fixed bug,
then an unexpected race is occurring, so return a temporary error
-EAGAIN instead.
This prevents callers such as __block_write_begin_int() from
requesting a read into a buffer that is not mapped, which would cause
the BUG_ON check for the BH_Mapped flag in submit_bh_wbc() to fail.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Fixes: 1f5abe7e7dbc ("nilfs2: replace BUG_ON and BUG calls triggerable from ioctl")
Cc: stable@xxxxxxxxxxxxxxx
---
fs/nilfs2/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 9c334c722fc1..5a888b2c1803 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -112,7 +112,7 @@ int nilfs_get_block(struct inode *inode, sector_t blkoff,
"%s (ino=%lu): a race condition while inserting a data block at offset=%llu",
__func__, inode->i_ino,
(unsigned long long)blkoff);
- err = 0;
+ err = -EAGAIN;
}
nilfs_transaction_abort(inode->i_sb);
goto out;
--
2.34.1
