linux-ext4 - [PATCH v3] ext4: Fix bdev write error check failed when mount fs with ro

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 27 Sep 2020 22:05:56 -0400
From:   Zhang Xiaoxu <zhangxiaoxu5@...wei.com>
To:     <yi.zhang@...wei.com>, <tytso@....edu>, <jack@...e.cz>,
        <linux-ext4@...r.kernel.org>
CC:     <adilger.kernel@...ger.ca>
Subject: [PATCH v3] ext4: Fix bdev write error check failed when mount fs with ro

Consider a situation when a filesystem was uncleanly shutdown and the
orphan list is not empty and a read-only mount is attempted. The orphan
list cleanup during mount will fail with:

ext4_check_bdev_write_error:193: comm mount: Error while async write back metadata

This happens because sbi->s_bdev_wb_err is not initialized when mounting
the filesystem in read only mode and so ext4_check_bdev_write_error()
falsely triggers.

Initialize sbi->s_bdev_wb_err unconditionally to avoid this problem.

Fixes: bc71726c7257 ("ext4: abort the filesystem if failed to async write metadata buffer")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@...wei.com>
Reviewed-by: Jan Kara <jack@...e.cz>
---
 fs/ext4/super.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index ea425b49b345..0303e6e17190 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4814,9 +4814,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	 * used to detect the metadata async write error.
 	 */
 	spin_lock_init(&sbi->s_bdev_wb_lock);
-	if (!sb_rdonly(sb))
-		errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
-					 &sbi->s_bdev_wb_err);
+	errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
+				 &sbi->s_bdev_wb_err);
 	sb->s_bdev->bd_super = sb;
 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
 	ext4_orphan_cleanup(sb, es);
@@ -5707,14 +5706,6 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
 				goto restore_opts;
 			}
 
-			/*
-			 * Update the original bdev mapping's wb_err value
-			 * which could be used to detect the metadata async
-			 * write error.
-			 */
-			errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
-						 &sbi->s_bdev_wb_err);
-
 			/*
 			 * Mounting a RDONLY partition read-write, so reread
 			 * and store the current valid flag.  (It may have
-- 
2.25.4