[PATCH 6.12 419/422] fs: fix adding security options to statmount.mnt_opt

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

commit 5eb987105357cb7cfa7cf3b1e2f66d5c0977e412 upstream.

Prepending security options was made conditional on sb->s_op->show_options,
but security options are independent of sb options.

Fixes: 056d33137bf9 ("fs: prepend statmount.mnt_opts string with security_sb_mnt_opts()")
Fixes: f9af549d1fd3 ("fs: export mount options via statmount()")
Cc: stable@xxxxxxxxxxxxxxx # v6.11
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20250129151253.33241-1-mszeredi@xxxxxxxxxx
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/namespace.c |   29 ++++++++++++++---------------
 1 file changed, 14 insertions(+), 15 deletions(-)

--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -5020,30 +5020,29 @@ static int statmount_mnt_opts(struct kst
 {
 	struct vfsmount *mnt = s->mnt;
 	struct super_block *sb = mnt->mnt_sb;
+	size_t start = seq->count;
 	int err;
 
-	if (sb->s_op->show_options) {
-		size_t start = seq->count;
-
-		err = security_sb_show_options(seq, sb);
-		if (err)
-			return err;
+	err = security_sb_show_options(seq, sb);
+	if (err)
+		return err;
 
+	if (sb->s_op->show_options) {
 		err = sb->s_op->show_options(seq, mnt->mnt_root);
 		if (err)
 			return err;
+	}
 
-		if (unlikely(seq_has_overflowed(seq)))
-			return -EAGAIN;
+	if (unlikely(seq_has_overflowed(seq)))
+		return -EAGAIN;
 
-		if (seq->count == start)
-			return 0;
+	if (seq->count == start)
+		return 0;
 
-		/* skip leading comma */
-		memmove(seq->buf + start, seq->buf + start + 1,
-			seq->count - start - 1);
-		seq->count--;
-	}
+	/* skip leading comma */
+	memmove(seq->buf + start, seq->buf + start + 1,
+		seq->count - start - 1);
+	seq->count--;
 
 	return 0;
 }