WTF: patch "[PATCH] landlock: Change landlock_restrict_self(2) check ordering" was seriously submitted to be applied to the 5.18-stable tree?

[<gregkh@linuxfoundation.org>]

The patch below was submitted to be applied to the 5.18-stable tree.

I fail to see how this patch meets the stable kernel rules as found at
Documentation/process/stable-kernel-rules.rst.

I could be totally wrong, and if so, please respond to 
<stable@vger.kernel.org> and let me know why this patch should be
applied.  Otherwise, it is now dropped from my patch queues, never to be
seen again.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From eba39ca4b155c54adf471a69e91799cc1727873f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= <mic@digikod.net>
Date: Fri, 6 May 2022 18:08:19 +0200
Subject: [PATCH] landlock: Change landlock_restrict_self(2) check ordering
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

According to the Landlock goal to be a security feature available to
unprivileges processes, it makes more sense to first check for
no_new_privs before checking anything else (i.e. syscall arguments).

Merge inval_fd_enforce and unpriv_enforce_without_no_new_privs tests
into the new restrict_self_checks_ordering.  This is similar to the
previous commit checking other syscalls.

Link: https://lore.kernel.org/r/20220506160820.524344-10-mic@digikod.net
Cc: stable@vger.kernel.org
Signed-off-by: Mickaël Salaün <mic@digikod.net>

diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c
index a7396220c9d4..507d43827afe 100644
--- a/security/landlock/syscalls.c
+++ b/security/landlock/syscalls.c
@@ -405,10 +405,6 @@ SYSCALL_DEFINE2(landlock_restrict_self, const int, ruleset_fd, const __u32,
 	if (!landlock_initialized)
 		return -EOPNOTSUPP;
 
-	/* No flag for now. */
-	if (flags)
-		return -EINVAL;
-
 	/*
 	 * Similar checks as for seccomp(2), except that an -EPERM may be
 	 * returned.
@@ -417,6 +413,10 @@ SYSCALL_DEFINE2(landlock_restrict_self, const int, ruleset_fd, const __u32,
 	    !ns_capable_noaudit(current_user_ns(), CAP_SYS_ADMIN))
 		return -EPERM;
 
+	/* No flag for now. */
+	if (flags)
+		return -EINVAL;
+
 	/* Gets and checks the ruleset. */
 	ruleset = get_ruleset_from_fd(ruleset_fd, FMODE_CAN_READ);
 	if (IS_ERR(ruleset))
diff --git a/tools/testing/selftests/landlock/base_test.c b/tools/testing/selftests/landlock/base_test.c
index 18b779471dcb..21fb33581419 100644
--- a/tools/testing/selftests/landlock/base_test.c
+++ b/tools/testing/selftests/landlock/base_test.c
@@ -168,22 +168,49 @@ TEST(add_rule_checks_ordering)
 	ASSERT_EQ(0, close(ruleset_fd));
 }
 
-TEST(inval_fd_enforce)
+/* Tests ordering of syscall argument and permission checks. */
+TEST(restrict_self_checks_ordering)
 {
+	const struct landlock_ruleset_attr ruleset_attr = {
+		.handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE,
+	};
+	struct landlock_path_beneath_attr path_beneath_attr = {
+		.allowed_access = LANDLOCK_ACCESS_FS_EXECUTE,
+		.parent_fd = -1,
+	};
+	const int ruleset_fd =
+		landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+
+	ASSERT_LE(0, ruleset_fd);
+	path_beneath_attr.parent_fd =
+		open("/tmp", O_PATH | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC);
+	ASSERT_LE(0, path_beneath_attr.parent_fd);
+	ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+				       &path_beneath_attr, 0));
+	ASSERT_EQ(0, close(path_beneath_attr.parent_fd));
+
+	/* Checks unprivileged enforcement without no_new_privs. */
+	drop_caps(_metadata);
+	ASSERT_EQ(-1, landlock_restrict_self(-1, -1));
+	ASSERT_EQ(EPERM, errno);
+	ASSERT_EQ(-1, landlock_restrict_self(-1, 0));
+	ASSERT_EQ(EPERM, errno);
+	ASSERT_EQ(-1, landlock_restrict_self(ruleset_fd, 0));
+	ASSERT_EQ(EPERM, errno);
+
 	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
 
+	/* Checks invalid flags. */
+	ASSERT_EQ(-1, landlock_restrict_self(-1, -1));
+	ASSERT_EQ(EINVAL, errno);
+
+	/* Checks invalid ruleset FD. */
 	ASSERT_EQ(-1, landlock_restrict_self(-1, 0));
 	ASSERT_EQ(EBADF, errno);
-}
-
-TEST(unpriv_enforce_without_no_new_privs)
-{
-	int err;
 
-	drop_caps(_metadata);
-	err = landlock_restrict_self(-1, 0);
-	ASSERT_EQ(EPERM, errno);
-	ASSERT_EQ(err, -1);
+	/* Checks valid call. */
+	ASSERT_EQ(0, landlock_restrict_self(ruleset_fd, 0));
+	ASSERT_EQ(0, close(ruleset_fd));
 }
 
 TEST(ruleset_fd_io)