Date:   Tue, 24 Jan 2023 15:41:55 -0800
In-Reply-To: <20230124234156.211569-1-avagin@google.com>
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References: <20230124234156.211569-1-avagin@google.com>
Message-ID: <20230124234156.211569-6-avagin@google.com>
Subject: [PATCH 5/6] selftest/seccomp: add a new test for the sync mode of seccomp_user_notify
From:   Andrei Vagin <avagin@google.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>,
        Christian Brauner <brauner@kernel.org>,
        Chen Yu <yu.c.chen@intel.com>, Andrei Vagin <avagin@gmail.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Peter Oskolkov <posk@google.com>,
        Tycho Andersen <tycho@tycho.pizza>,
        Will Drewry <wad@chromium.org>,
        Vincent Guittot <vincent.guittot@linaro.org>
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From: Andrei Vagin <avagin@gmail.com>

Test output:
 #  RUN           global.user_notification_sync ...
 #            OK  global.user_notification_sync
 ok 51 global.user_notification_sync

Signed-off-by: Andrei Vagin <avagin@gmail.com>
---
 tools/testing/selftests/seccomp/seccomp_bpf.c | 55 +++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 9c2f448bb3a9..05b8de6d1fcb 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -4243,6 +4243,61 @@ TEST(user_notification_addfd_rlimit)
 	close(memfd);
 }
 
+#ifndef SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP
+#define SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP (1UL << 0)
+#define SECCOMP_IOCTL_NOTIF_SET_FLAGS  SECCOMP_IOW(4, __u64)
+#endif
+
+TEST(user_notification_sync)
+{
+	struct seccomp_notif req = {};
+	struct seccomp_notif_resp resp = {};
+	int status, listener;
+	pid_t pid;
+	long ret;
+
+	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+	ASSERT_EQ(0, ret) {
+		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
+	}
+
+	listener = user_notif_syscall(__NR_getppid,
+				      SECCOMP_FILTER_FLAG_NEW_LISTENER);
+	ASSERT_GE(listener, 0);
+
+	/* Try to set invalid flags. */
+	EXPECT_SYSCALL_RETURN(-EINVAL,
+		ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS, 0xffffffff, 0));
+
+	ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS,
+			SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP, 0), 0);
+
+	pid = fork();
+	ASSERT_GE(pid, 0);
+	if (pid == 0) {
+		ret = syscall(__NR_getppid);
+		ASSERT_EQ(ret, USER_NOTIF_MAGIC) {
+			_exit(1);
+		}
+		_exit(0);
+	}
+
+	req.pid = 0;
+	ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
+
+	ASSERT_EQ(req.data.nr,  __NR_getppid);
+
+	resp.id = req.id;
+	resp.error = 0;
+	resp.val = USER_NOTIF_MAGIC;
+	resp.flags = 0;
+	ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
+
+	ASSERT_EQ(waitpid(pid, &status, 0), pid);
+	ASSERT_EQ(status, 0);
+}
+
+
 /* Make sure PTRACE_O_SUSPEND_SECCOMP requires CAP_SYS_ADMIN. */
 FIXTURE(O_SUSPEND_SECCOMP) {
 	pid_t pid;
-- 
2.39.1.405.gd4c25cc71f-goog