[LTP] [PATCH 7/8] containers/timens: Add basic error test

[Cyril Hrubis]

Add basic error handling test for the /proc/$PID/timens_offsets file.

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
---
 runtest/containers                            |  1 +
 testcases/kernel/containers/timens/.gitignore |  1 +
 testcases/kernel/containers/timens/Makefile   |  6 ++
 testcases/kernel/containers/timens/timens01.c | 75 +++++++++++++++++++
 4 files changed, 83 insertions(+)
 create mode 100644 testcases/kernel/containers/timens/.gitignore
 create mode 100644 testcases/kernel/containers/timens/Makefile
 create mode 100644 testcases/kernel/containers/timens/timens01.c

diff --git a/runtest/containers b/runtest/containers
index 1006d8d35..23e4a533d 100644
--- a/runtest/containers
+++ b/runtest/containers
@@ -90,3 +90,4 @@ userns07 userns07
 sysinfo03 sysinfo03
 clock_nanosleep03 clock_nanosleep03
 clock_gettime03 clock_gettime03
+timens01 timens01
diff --git a/testcases/kernel/containers/timens/.gitignore b/testcases/kernel/containers/timens/.gitignore
new file mode 100644
index 000000000..bcd2dd9dd
--- /dev/null
+++ b/testcases/kernel/containers/timens/.gitignore
@@ -0,0 +1 @@
+timens01
diff --git a/testcases/kernel/containers/timens/Makefile b/testcases/kernel/containers/timens/Makefile
new file mode 100644
index 000000000..5ea7d67db
--- /dev/null
+++ b/testcases/kernel/containers/timens/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+top_srcdir		?= ../../../..
+
+include $(top_srcdir)/include/mk/testcases.mk
+include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/kernel/containers/timens/timens01.c b/testcases/kernel/containers/timens/timens01.c
new file mode 100644
index 000000000..08bc449f9
--- /dev/null
+++ b/testcases/kernel/containers/timens/timens01.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+
+  Copyright (c) 2020 Cyril Hrubis <chrubis@suse.cz>
+
+ */
+/*
+
+  Basic test for timens_offsets error handling.
+
+  After a call to unshare(CLONE_NEWTIME) a new timer namespace is created, the
+  process that has called the unshare() can adjust offsets for CLOCK_MONOTONIC
+  and CLOCK_BOOTTIME for its children by writing to the '/proc/self/timens_offsets'.
+
+ */
+
+#define _GNU_SOURCE
+#include "lapi/setns.h"
+#include "lapi/namespaces_constants.h"
+#include "lapi/posix_clocks.h"
+#include "tst_test.h"
+
+static struct tcase {
+	const char *offsets;
+	int exp_err;
+} tcases[] = {
+	/* obvious garbage */
+	{"not an offset", EINVAL},
+	/* missing nanoseconds */
+	{"1 10", EINVAL},
+	/* negative nanoseconds */
+	{"1 10 -10", EINVAL},
+	/* nanoseconds > 1s */
+	{"1 10 1000000001", EINVAL},
+	/* unsupported CLOCK_REALTIME */
+	{"0 10 0", EINVAL},
+	/* mess on the second line */
+	{"1 10 0\na", EINVAL},
+	/* overflow kernel 64bit nanosecond timer */
+	{"1 9223372036 0", ERANGE},
+	{"1 -9223372036 0", ERANGE},
+};
+
+static void verify_ns_clock(unsigned int n)
+{
+	struct tcase *tc = &tcases[n];
+	int fd, ret;
+
+	SAFE_UNSHARE(CLONE_NEWTIME);
+
+	fd = SAFE_OPEN("/proc/self/timens_offsets", O_WRONLY);
+	ret = write(fd, tc->offsets, strlen(tc->offsets));
+
+	if (ret != -1) {
+		tst_res(TFAIL, "Write returned %i", ret);
+		return;
+	}
+
+	if (errno != tc->exp_err) {
+		tst_res(TFAIL | TERRNO, "Write should fail with %s, got:",
+			tst_strerrno(tc->exp_err));
+		return;
+	}
+
+	tst_res(TPASS | TERRNO, "Write offsets='%s'", tc->offsets);
+}
+
+static struct tst_test test = {
+	.tcnt = ARRAY_SIZE(tcases),
+	.test = verify_ns_clock,
+	.needs_root = 1,
+	.needs_kconfigs = (const char *[]) {
+		"CONFIG_TIME_NS=y"
+	}
+};
-- 
2.23.0