[Devel] [PATCH vz10 2/2] fs: fix adding security options to statmount.mnt_opt

[Eva Kurchatova]

From: Miklos Szeredi <mszeredi at redhat.com>

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 at vger.kernel.org # v6.11
Signed-off-by: Miklos Szeredi <mszeredi at redhat.com>
Link: https://lore.kernel.org/r/20250129151253.33241-1-mszeredi@redhat.com
Signed-off-by: Christian Brauner <brauner at kernel.org>

(cherry picked from commit 5eb987105357cb7cfa7cf3b1e2f66d5c0977e412)
Signed-off-by: Eva Kurchatova <eva.kurchatova at virtuozzo.com>

https://virtuozzo.atlassian.net/browse/VSTOR-132443
Feature: Fix selftests
---
 fs/namespace.c | 29 ++++++++++++++---------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/fs/namespace.c b/fs/namespace.c
index 8f8161a555a6..a66e074c68a9 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -5302,30 +5302,29 @@ static int statmount_mnt_opts(struct kstatmount *s, struct seq_file *seq)
 {
 	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;
 }
-- 
2.54.0