From 6b992ff25658367089db4a82666e232b65d55eae Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Thu, 30 Oct 2014 10:53:16 -0400 Subject: [PATCH] ext4: disallow changing journal_csum option during remount ext4 does not permit changing the metadata or journal checksum feature flag while mounted. Until we decide to support that, don't allow a remount to change the journal_csum flag (right now we silently fail to change anything). Signed-off-by: Darrick J. Wong Signed-off-by: Theodore Ts'o --- fs/ext4/super.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 5c11e2153e36..96059e0ef165 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4845,6 +4845,14 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) goto restore_opts; } + if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^ + test_opt(sb, JOURNAL_CHECKSUM)) { + ext4_msg(sb, KERN_ERR, "changing journal_checksum " + "during remount not supported"); + err = -EINVAL; + goto restore_opts; + } + if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) { if (test_opt2(sb, EXPLICIT_DELALLOC)) { ext4_msg(sb, KERN_ERR, "can't mount with " -- 2.34.1