1 files changed, 57 insertions, 14 deletions

diff --git a/tools/testing/selftests/memfd/memfd_test.c b/tools/testing/selftests/memfd/memfd_test.c
index 3df008677239..5b993924cc3f 100644
--- a/tools/testing/selftests/memfd/memfd_test.c
+++ b/tools/testing/selftests/memfd/memfd_test.c
@@ -9,6 +9,7 @@
 #include <fcntl.h>
 #include <linux/memfd.h>
 #include <sched.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <signal.h>
@@ -44,8 +45,6 @@
  */
 static size_t mfd_def_size = MFD_DEF_SIZE;
 static const char *memfd_str = MEMFD_STR;
-static int newpid_thread_fn2(void *arg);
-static void join_newpid_thread(pid_t pid);
 
 static ssize_t fd2name(int fd, char *buf, size_t bufsize)
 {
@@ -172,7 +171,7 @@ static void mfd_fail_new(const char *name, unsigned int flags)
 	r = sys_memfd_create(name, flags);
 	if (r >= 0) {
 		printf("memfd_create(\"%s\", %u) succeeded, but failure expected\n",
-		       name, flags);
+		       name ? name : "NULL", flags);
 		close(r);
 		abort();
 	}
@@ -194,7 +193,6 @@ static unsigned int mfd_assert_get_seals(int fd)
 static void mfd_assert_has_seals(int fd, unsigned int seals)
 {
 	char buf[PATH_MAX];
-	int nbytes;
 	unsigned int s;
 	fd2name(fd, buf, PATH_MAX);
 
@@ -284,6 +282,24 @@ static void *mfd_assert_mmap_shared(int fd)
 	return p;
 }
 
+static void *mfd_assert_mmap_read_shared(int fd)
+{
+	void *p;
+
+	p = mmap(NULL,
+		 mfd_def_size,
+		 PROT_READ,
+		 MAP_SHARED,
+		 fd,
+		 0);
+	if (p == MAP_FAILED) {
+		printf("mmap() failed: %m\n");
+		abort();
+	}
+
+	return p;
+}
+
 static void *mfd_assert_mmap_private(int fd)
 {
 	void *p;
@@ -696,7 +712,6 @@ static void mfd_assert_mode(int fd, int mode)
 {
 	struct stat st;
 	char buf[PATH_MAX];
-	int nbytes;
 
 	fd2name(fd, buf, PATH_MAX);
 
@@ -715,7 +730,6 @@ static void mfd_assert_mode(int fd, int mode)
 static void mfd_assert_chmod(int fd, int mode)
 {
 	char buf[PATH_MAX];
-	int nbytes;
 
 	fd2name(fd, buf, PATH_MAX);
 
@@ -731,7 +745,6 @@ static void mfd_fail_chmod(int fd, int mode)
 {
 	struct stat st;
 	char buf[PATH_MAX];
-	int nbytes;
 
 	fd2name(fd, buf, PATH_MAX);
 
@@ -985,6 +998,30 @@ static void test_seal_future_write(void)
 	close(fd);
 }
 
+static void test_seal_write_map_read_shared(void)
+{
+	int fd;
+	void *p;
+
+	printf("%s SEAL-WRITE-MAP-READ\n", memfd_str);
+
+	fd = mfd_assert_new("kern_memfd_seal_write_map_read",
+			    mfd_def_size,
+			    MFD_CLOEXEC | MFD_ALLOW_SEALING);
+
+	mfd_assert_add_seals(fd, F_SEAL_WRITE);
+	mfd_assert_has_seals(fd, F_SEAL_WRITE);
+
+	p = mfd_assert_mmap_read_shared(fd);
+
+	mfd_assert_read(fd);
+	mfd_assert_read_shared(fd);
+	mfd_fail_write(fd);
+
+	munmap(p, mfd_def_size);
+	close(fd);
+}
+
 /*
  * Test SEAL_SHRINK
  * Test whether SEAL_SHRINK actually prevents shrinking
@@ -1254,9 +1291,6 @@ static void test_sysctl_set_sysctl2(void)
 
 static int sysctl_simple_child(void *arg)
 {
-	int fd;
-	int pid;
-
 	printf("%s sysctl 0\n", memfd_str);
 	test_sysctl_set_sysctl0();
 
@@ -1321,7 +1355,6 @@ static void test_sysctl_sysctl2_failset(void)
 
 static int sysctl_nested_child(void *arg)
 {
-	int fd;
 	int pid;
 
 	printf("%s nested sysctl 0\n", memfd_str);
@@ -1538,7 +1571,7 @@ static void test_share_open(char *banner, char *b_suffix)
 
 /*
  * Test sharing via fork()
- * Test whether seal-modifications work as expected with forked childs.
+ * Test whether seal-modifications work as expected with forked children.
  */
 static void test_share_fork(char *banner, char *b_suffix)
 {
@@ -1567,6 +1600,11 @@ static void test_share_fork(char *banner, char *b_suffix)
 	close(fd);
 }
 
+static bool pid_ns_supported(void)
+{
+	return access("/proc/self/ns/pid", F_OK) == 0;
+}
+
 int main(int argc, char **argv)
 {
 	pid_t pid;
@@ -1597,12 +1635,17 @@ int main(int argc, char **argv)
 
 	test_seal_write();
 	test_seal_future_write();
+	test_seal_write_map_read_shared();
 	test_seal_shrink();
 	test_seal_grow();
 	test_seal_resize();
 
-	test_sysctl_simple();
-	test_sysctl_nested();
+	if (pid_ns_supported()) {
+		test_sysctl_simple();
+		test_sysctl_nested();
+	} else {
+		printf("PID namespaces are not supported; skipping sysctl tests\n");
+	}
 
 	test_share_dup("SHARE-DUP", "");
 	test_share_mmap("SHARE-MMAP", "");