[CRIU] [PATCH v2 23/30] zdtm: Add userns-leaked-sock test

[Kirill Tkhai]

1)Create a socket, bind it, then create a child in lower user, pid and net ns.
2)Close socket in parent
3)After signal, check that child can create the socket with the same name.
  (It must, as it's in another net namespace).

v2: Add uid/gid mapping.

Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
---
 test/zdtm/static/Makefile                |    1 
 test/zdtm/static/userns-leaked-sock.c    |  164 ++++++++++++++++++++++++++++++
 test/zdtm/static/userns-leaked-sock.desc |    1 
 3 files changed, 166 insertions(+)
 create mode 100644 test/zdtm/static/userns-leaked-sock.c
 create mode 100644 test/zdtm/static/userns-leaked-sock.desc

diff --git a/test/zdtm/static/Makefile b/test/zdtm/static/Makefile
index 0ea6c3d87..31ba6d590 100644
--- a/test/zdtm/static/Makefile
+++ b/test/zdtm/static/Makefile
@@ -176,6 +176,7 @@ TST_NOFILE	:=				\
 		userns00			\
 		userns01			\
 		userns02			\
+		userns-leaked-sock		\
 		netns_sub_veth			\
 		pidns00				\
 		pidns01				\
diff --git a/test/zdtm/static/userns-leaked-sock.c b/test/zdtm/static/userns-leaked-sock.c
new file mode 100644
index 000000000..8a84efe6a
--- /dev/null
+++ b/test/zdtm/static/userns-leaked-sock.c
@@ -0,0 +1,164 @@
+#include <stdbool.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <sched.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include "zdtmtst.h"
+#include "lock.h"
+
+const char *test_doc	= "Check that restorer for sockets is choosed right in dependence of net_ns->user_ns";
+const char *test_author	= "Kirill Tkhai <ktkhai at virtuozzo.com>";
+
+enum {
+	FUTEX_INITIALIZED = 0,
+	MAPS_SET,
+	CHILD_PREPARED,
+	POST_RESTORE_CHECK,
+	EMERGENCY_ABORT,
+};
+
+futex_t *futex;
+
+int write_map(pid_t pid, char *file, char *map)
+{
+	char path[PATH_MAX];
+	int fd, ret;
+
+	sprintf(path, "/proc/%d/%s", pid, file);
+	fd = open(path, O_WRONLY);
+	if (fd < 0) {
+		fail("Can't open");
+		return -1;
+	}
+	ret = write(fd, map, strlen(map));
+	if (ret != strlen(map)) {
+		fail("Can't write");
+		close(fd);
+		return -1;
+	}
+	close(fd);
+
+	return 0;
+}
+
+int child_fn(void *arg)
+{
+	int sk, orig_sk = (int)(long)arg;
+	struct sockaddr_un addr;
+	socklen_t len = sizeof(addr);
+
+	if (getsockname(orig_sk, &addr, &len) < 0) {
+		pr_perror("getsockname()");
+		goto err;
+	}
+	futex_wait_while_lt(futex, MAPS_SET);
+	if (futex_get(futex) == EMERGENCY_ABORT)
+		return 1;
+
+	if (setuid(0)) {
+		pr_perror("Can't set uid");
+		goto err;
+	}
+	if (setgid(0)) {
+		pr_perror("Can't set gid");
+		goto err;
+	}
+
+	futex_set_and_wake(futex, CHILD_PREPARED);
+	futex_wait_while_lt(futex, POST_RESTORE_CHECK);
+
+	sk = socket(PF_UNIX, SOCK_DGRAM, 0);
+	if (sk < 0) {
+		pr_perror("socket");
+		goto err;
+	}
+
+	/* This must complete w/o errors, as orig_sk is from another net namespace */
+	if (bind(sk, (struct sockaddr *)&addr, len) < 0) {
+		pr_perror("bind");
+		goto err;
+	}
+
+	return 0;
+err:
+	futex_set_and_wake(futex, EMERGENCY_ABORT);
+	return 1;
+}
+
+int main(int argc, char **argv)
+{
+	struct sockaddr_un addr;
+	int sk, len;
+	int status;
+	pid_t pid;
+
+	test_init(argc, argv);
+	futex = mmap(NULL, sizeof(*futex), PROT_WRITE | PROT_READ, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+	if (futex == MAP_FAILED) {
+		fail("mmap futex\n");
+		return 1;
+	}
+	futex_init(futex);
+
+	sk = socket(PF_UNIX, SOCK_DGRAM, 0);
+	if (sk < 0) {
+		fail("socket");
+		return 1;
+	}
+
+	addr.sun_family = AF_UNIX;
+	sprintf(addr.sun_path, "x/test-socket-name");
+	len = SUN_LEN(&addr);
+	*addr.sun_path = '\0';
+
+	if (bind(sk, (struct sockaddr *)&addr, len) < 0) {
+		fail("bind");
+		return 1;
+	}
+
+	{
+		char stack;
+		pid = clone(child_fn, &stack - 256, CLONE_NEWUSER|CLONE_NEWNET|CLONE_NEWPID, (void *)(long)sk);
+		if (pid == -1) {
+			fail("clone");
+			return 1;
+		}
+	}
+
+	if (write_map(pid, "uid_map", "0 10 1") < 0 ||
+	    write_map(pid, "gid_map", "0 12 1") < 0) {
+		fail("write map");
+		goto err;
+	}
+
+	futex_set_and_wake(futex, MAPS_SET);
+	futex_wait_while_lt(futex, CHILD_PREPARED);
+
+	close(sk);
+
+	test_daemon();
+	test_waitsig();
+
+	futex_set_and_wake(futex, POST_RESTORE_CHECK);
+
+	if (wait(&status) < 0 || WEXITSTATUS(status)) {
+		fail("pid: status=%d\n", WEXITSTATUS(status));
+		goto err;
+	}
+
+	pass();
+	return 0;
+err:
+	futex_set_and_wake(futex, EMERGENCY_ABORT);
+	wait(&status);
+	return 1;
+}
diff --git a/test/zdtm/static/userns-leaked-sock.desc b/test/zdtm/static/userns-leaked-sock.desc
new file mode 100644
index 000000000..703c925e2
--- /dev/null
+++ b/test/zdtm/static/userns-leaked-sock.desc
@@ -0,0 +1 @@
+{'flavor': 'uns', 'flags': 'suid', 'feature': 'ns_pid ns_get_parent ns_get_userns'}