From: Jan Kara jack@suse.cz

mainline inclusion from mainline-v6.12-rc3 commit 76486b104168ae59703190566e372badf433314b category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB2YWS CVE: CVE-2024-50191

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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When we remount filesystem with 'abort' mount option while changing other mount options as well (as is LTP test doing), we can return error from the system call after commit d3476f3dad4a ("ext4: don't set SB_RDONLY after filesystem errors") because the application of mount option changes detects shutdown filesystem and refuses to do anything. The behavior of application of other mount options in presence of 'abort' mount option is currently rather arbitary as some mount option changes are handled before 'abort' and some after it.

Move aborting of the filesystem to the end of remount handling so all requested changes are properly applied before the filesystem is shutdown to have a reasonably consistent behavior.

Fixes: d3476f3dad4a ("ext4: don't set SB_RDONLY after filesystem errors") Reported-by: Jan Stancek jstancek@redhat.com Link: https://lore.kernel.org/all/Zvp6L+oFnfASaoHl@t14s Signed-off-by: Jan Kara jack@suse.cz Tested-by: Jan Stancek jstancek@redhat.com Link: https://patch.msgid.link/20241004221556.19222-1-jack@suse.cz Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Yongjian Sun sunyongjian1@huawei.com --- fs/ext4/super.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 367fa50be4d6..5c52881160e5 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -6662,9 +6662,6 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb) goto restore_opts; }

- if (test_opt2(sb, ABORT)) - ext4_abort(sb, ESHUTDOWN, "Abort forced by user"); - sb->s_flags = (sb->s_flags & ~SB_POSIXACL) | (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);

@@ -6833,6 +6830,14 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb) if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb)) ext4_stop_mmpd(sbi);

+ /* + * Handle aborting the filesystem as the last thing during remount to + * avoid obsure errors during remount when some option changes fail to + * apply due to shutdown filesystem. + */ + if (test_opt2(sb, ABORT)) + ext4_abort(sb, ESHUTDOWN, "Abort forced by user"); + return 0;

restore_opts: