From: Christian Brauner <brauner@kernel.org>
Date: Wed, 17 Sep 2025 10:28:05 +0000 (+0200)
Subject: mnt: simplify ns_common_init() handling
X-Git-Tag: v6.18-rc1~232^2~5^2~3
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=86cdbae5c61c6b8c0a2adc78dbbb0314b3254a9c;p=thirdparty%2Flinux.git

mnt: simplify ns_common_init() handling

Assign the reserved MNT_NS_ANON_INO sentinel to anonymous mount
namespaces and cleanup the initial mount ns allocation. This is just a
preparatory patch and the ns->inum check in ns_common_init() will be
dropped in the next patch.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
---

diff --git a/fs/namespace.c b/fs/namespace.c
index f0bddc9cf2a6d..b2fcb901ad8c1 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -4103,6 +4103,8 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns, bool a
 		return ERR_PTR(-ENOMEM);
 	}
 
+	if (anon)
+		new_ns->ns.inum = MNT_NS_ANON_INO;
 	ret = ns_common_init(&new_ns->ns, &mntns_operations, !anon);
 	if (ret) {
 		kfree(new_ns);
diff --git a/kernel/nscommon.c b/kernel/nscommon.c
index ebf4783d05054..e10fad8afe61b 100644
--- a/kernel/nscommon.c
+++ b/kernel/nscommon.c
@@ -5,7 +5,7 @@
 int ns_common_init(struct ns_common *ns, const struct proc_ns_operations *ops,
 		   bool alloc_inum)
 {
-	if (alloc_inum) {
+	if (alloc_inum && !ns->inum) {
 		int ret;
 		ret = proc_alloc_inum(&ns->inum);
 		if (ret)