[v2,03/36] zdtm: Add userns00 test

Submitted by Kirill Tkhai on Feb. 3, 2017, 4:12 p.m.

Details

Message ID 148613832362.3612.13952959527243699109.stgit@localhost.localdomain
State New
Series "Nested user namespaces support"
Headers show

Commit Message

Kirill Tkhai Feb. 3, 2017, 4:12 p.m.
Create two children, and unshare() user_ns in one of them (C1).
The second child creates one more process, which switches to C1's
namespace and unshares.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
---
 test/zdtm/static/Makefile      |    1 
 test/zdtm/static/userns00.c    |  289 ++++++++++++++++++++++++++++++++++++++++
 test/zdtm/static/userns00.desc |    1 
 3 files changed, 291 insertions(+)
 create mode 100644 test/zdtm/static/userns00.c
 create mode 100644 test/zdtm/static/userns00.desc

Patch hide | download patch | download mbox

diff --git a/test/zdtm/static/Makefile b/test/zdtm/static/Makefile
index c24ee8f69..7d773b456 100644
--- a/test/zdtm/static/Makefile
+++ b/test/zdtm/static/Makefile
@@ -172,6 +172,7 @@  TST_NOFILE	:=				\
 		macvlan			\
 		cr_veth				\
 		sock_peercred			\
+		userns00			\
 #		jobctl00			\
 
 ifneq ($(SRCARCH),arm)
diff --git a/test/zdtm/static/userns00.c b/test/zdtm/static/userns00.c
new file mode 100644
index 000000000..ea98f0b3b
--- /dev/null
+++ b/test/zdtm/static/userns00.c
@@ -0,0 +1,289 @@ 
+#define _GNU_SOURCE
+#include <stdbool.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <sched.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <dirent.h>
+
+#include "zdtmtst.h"
+#include "lock.h"
+
+/*
+ * The test creates the following items.
+ *
+ *  Processes hierarhy with their namespaces (in brackets):
+ *                 Parent (ns_p)
+ *                /      \
+ *    (ns_c1) Child1    Child2 (ns_p)
+ *                        |
+ *                    GrandChild (ns_gc)
+ *
+ *  Namespaces hierarhy:
+ *         ns_p
+ *           |
+ *         ns_c1
+ *           |
+ *         ns_gc
+ */
+const char *test_doc	= "Check user namespaces remain the same over process tree";
+const char *test_author	= "Kirill Tkhai <ktkhai@virtuozzo.com>";
+
+enum {
+	FUTEX_INITIALIZED = 0,
+	CHILD1_CREATED,
+	GRAND_CHILD_PID_WRITTEN,
+	GRAND_CHILD_CREATED,
+	GRAND_CHILD_SETUP,
+	POST_RESTORE_CHECK,
+	EMERGENCY_ABORT,
+};
+
+volatile pid_t *grand_child_pid;
+futex_t *futex;
+
+int get_user_ns(pid_t pid, unsigned int *ns_id)
+{
+	char path[PATH_MAX], buf[PATH_MAX];
+	int len;
+
+	sprintf(path, "/proc/%d/ns/user", pid);
+	len = readlink(path, buf, PATH_MAX);
+	if (len < 0) {
+		pr_perror("Can't read link %s\n", path);
+		return -1;
+	}
+
+	buf[len] = '\0';
+	if (sscanf(buf, "user:[%u", ns_id) < 1) {
+		pr_err("Can't get id: %s\n", buf);
+		return -1;
+	}
+
+	return 0;
+}
+
+int write_map(pid_t pid, char *map)
+{
+	char path[PATH_MAX];
+	int fd, ret;
+
+	sprintf(path, "/proc/%d/%s", pid, map);
+	fd = open(path, O_WRONLY);
+	if (fd < 0) {
+		fail("Can't open");
+		return -1;
+	}
+	ret = write(fd, "0 0 1\n", 6);
+	if (ret != 6) {
+		fail("Can't write");
+		return -1;
+	}
+	close(fd);
+
+	return 0;
+}
+
+/* Child1 creates its own namespace */
+int child1(void)
+{
+	int ret;
+
+	ret = unshare(CLONE_NEWUSER);
+	if (ret < 0) {
+		pr_perror("unshare");
+		futex_set_and_wake(futex, EMERGENCY_ABORT);
+		return 1;
+	}
+
+	futex_set_and_wake(futex, CHILD1_CREATED);
+	futex_wait_while_lt(futex, GRAND_CHILD_CREATED);
+
+	if (write_map(*grand_child_pid, "uid_map") < 0 ||
+	    write_map(*grand_child_pid, "gid_map") < 0) {
+		fail("write map");
+		futex_set_and_wake(futex, EMERGENCY_ABORT);
+		return 2;
+	}
+
+	futex_set_and_wake(futex, GRAND_CHILD_SETUP);
+	futex_wait_while_lt(futex, POST_RESTORE_CHECK);
+
+	return 0;
+}
+
+/* GrandChild switches to Child1 namespace and unshares */
+int grand_child(pid_t pid1)
+{
+	char path[PATH_MAX];
+	int fd = -1, ret;
+
+	futex_wait_while_lt(futex, GRAND_CHILD_PID_WRITTEN);
+
+	sprintf(path, "/proc/%d/ns/user", pid1);
+	fd = open(path, O_RDONLY);
+	if (fd < 0) {
+		pr_perror("open");
+		ret = 1;
+		goto err;
+	}
+
+	if (setns(fd, CLONE_NEWUSER) < 0) {
+		pr_perror("setns()");
+		ret = 2;
+		goto err;
+	}
+	close(fd);
+	fd = -1;
+
+	if (setuid(0) || setgid(0)) {
+		pr_perror("setxids");
+		ret = 3;
+		goto err;
+	}
+
+	if (unshare(CLONE_NEWUSER) < 0) {
+		pr_perror("unshare");
+		ret = 3;
+		goto err;
+	}
+
+	futex_set_and_wake(futex, GRAND_CHILD_CREATED);
+	futex_wait_while_lt(futex, POST_RESTORE_CHECK);
+
+	return 0;
+err:
+	futex_set_and_wake(futex, EMERGENCY_ABORT);
+	if (fd >= 0)
+		close(fd);
+	return ret;
+}
+
+/*
+ * Child2 remains in the namespace of the parent task,
+ * while its descendant GrandChild enters to Child1's
+ * namespace and unshares.
+ */
+int child2(pid_t pid1)
+{
+	int status, ret;
+	pid_t gc_pid;
+
+	gc_pid = fork();
+	if (gc_pid < 0) {
+		pr_perror("Can't fork");
+		ret = 1;
+		goto err;
+	} else if (gc_pid == 0)
+		exit(grand_child(pid1));
+
+	*grand_child_pid = gc_pid;
+	futex_set_and_wake(futex, GRAND_CHILD_PID_WRITTEN);
+	futex_wait_while_lt(futex, POST_RESTORE_CHECK);
+
+	if (wait(&status) != *grand_child_pid) {
+		pr_perror("Failed to wait grand child");
+		ret = 3;
+		goto err;
+	}
+
+	if (WEXITSTATUS(status)) {
+		pr_err("Grand child exited with %d\n", WEXITSTATUS(status));
+		ret = 4;
+		goto err;
+	}
+
+	return 0;
+err:
+	futex_set_and_wake(futex, EMERGENCY_ABORT);
+	if (*grand_child_pid > 0)
+		wait(&status);
+	return ret;
+}
+
+
+int main(int argc, char **argv)
+{
+	pid_t my_pid, pid1 = -1, pid2 = -1;
+	unsigned int ns_p, ns_c1, ns_c2;
+	int status;
+
+	test_init(argc, argv);
+	futex = mmap(NULL, sizeof(*futex) + sizeof(*grand_child_pid), PROT_WRITE | PROT_READ,
+								      MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+	grand_child_pid = (void *)futex + sizeof(*futex);
+	if (futex == MAP_FAILED) {
+		fail("mmap futex\n");
+		return 1;
+	}
+	futex_init(futex);
+	my_pid = getpid();
+
+	pid1 = fork();
+	if (pid1 == -1) {
+		fail("fork");
+		return 1;
+	} else if (pid1 == 0)
+		exit(child1());
+
+	futex_wait_while_lt(futex, CHILD1_CREATED);
+
+	if (write_map(pid1, "uid_map") < 0 ||
+	    write_map(pid1, "gid_map") < 0) {
+		fail("write map");
+		goto err;
+	}
+
+	pid2 = fork();
+	if (pid2 == -1) {
+		fail("fork");
+		goto err;
+	} else if (pid2 == 0)
+		exit(child2(pid1));
+
+	futex_wait_while_lt(futex, GRAND_CHILD_SETUP);
+	test_daemon();
+	test_waitsig();
+
+	if (get_user_ns(my_pid, &ns_p) < 0 ||
+	    get_user_ns(pid1, &ns_c1) < 0 ||
+	    get_user_ns(pid2, &ns_c2) < 0) {
+		fail("Can't get user ns\n");
+		goto err;
+	}
+
+	if (ns_p == ns_c1 || ns_p != ns_c2) {
+		fail("ns_p=%u, ns_c1=%u, ns_c2=%u\n", ns_p, ns_c1, ns_c2);
+		goto err;
+	}
+
+	futex_set_and_wake(futex, POST_RESTORE_CHECK);
+
+	errno = 0;
+	if (waitpid(pid1, &status, 0) < 0 || WEXITSTATUS(status)) {
+		fail("pid1: status=%d\n", WEXITSTATUS(status));
+		goto err;
+	}
+
+	if (waitpid(pid2, &status, 0) < 0 || WEXITSTATUS(status)) {
+		fail("pid2: status=%d\n", WEXITSTATUS(status));
+		goto err;
+	}
+	pass();
+	return 0;
+err:
+	futex_set_and_wake(futex, EMERGENCY_ABORT);
+	if (pid1 > 0)
+		wait(&status);
+	if (pid2 > 0)
+		wait(&status);
+	return 1;
+}
diff --git a/test/zdtm/static/userns00.desc b/test/zdtm/static/userns00.desc
new file mode 100644
index 000000000..1f8bec515
--- /dev/null
+++ b/test/zdtm/static/userns00.desc
@@ -0,0 +1 @@ 
+{'flavor': 'uns', 'flags': 'suid noauto'}