lkml.org 
[lkml]   [2024]   [Mar]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] nilfs2: prevent kernel bug at submit_bh_wbc()
Date
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@gmail.com>
Fixes: 1f5abe7e7dbc ("nilfs2: replace BUG_ON and BUG calls triggerable from ioctl")
Cc: stable@vger.kernel.org
---
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

\
 
 \ /
  Last update: 2024-03-13 11:59    [W:0.073 / U:0.716 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site