1 files changed, 21 insertions, 25 deletions

diff --git a/tools/testing/selftests/wireguard/qemu/init.c b/tools/testing/selftests/wireguard/qemu/init.c
index c9698120ac9d..3e49924dd77e 100644
--- a/tools/testing/selftests/wireguard/qemu/init.c
+++ b/tools/testing/selftests/wireguard/qemu/init.c
@@ -11,6 +11,7 @@
 #include <stdlib.h>
 #include <stdbool.h>
 #include <fcntl.h>
+#include <time.h>
 #include <sys/wait.h>
 #include <sys/mount.h>
 #include <sys/stat.h>
@@ -21,6 +22,7 @@
 #include <sys/utsname.h>
 #include <sys/sendfile.h>
 #include <sys/sysmacros.h>
+#include <sys/random.h>
 #include <linux/random.h>
 #include <linux/version.h>
 
@@ -56,29 +58,28 @@ static void print_banner(void)
 
 static void seed_rng(void)
 {
-	int fd;
-	struct {
-		int entropy_count;
-		int buffer_size;
-		unsigned char buffer[256];
-	} entropy = {
-		.entropy_count = sizeof(entropy.buffer) * 8,
-		.buffer_size = sizeof(entropy.buffer),
-		.buffer = "Adding real entropy is not actually important for these tests. Don't try this at home, kids!"
-	};
+	int bits = 256, fd;
 
-	if (mknod("/dev/urandom", S_IFCHR | 0644, makedev(1, 9)))
-		panic("mknod(/dev/urandom)");
-	fd = open("/dev/urandom", O_WRONLY);
+	if (!getrandom(NULL, 0, GRND_NONBLOCK))
+		return;
+	pretty_message("[+] Fake seeding RNG...");
+	fd = open("/dev/random", O_WRONLY);
 	if (fd < 0)
-		panic("open(urandom)");
-	for (int i = 0; i < 256; ++i) {
-		if (ioctl(fd, RNDADDENTROPY, &entropy) < 0)
-			panic("ioctl(urandom)");
-	}
+		panic("open(random)");
+	if (ioctl(fd, RNDADDTOENTCNT, &bits) < 0)
+		panic("ioctl(RNDADDTOENTCNT)");
 	close(fd);
 }
 
+static void set_time(void)
+{
+	if (time(NULL))
+		return;
+	pretty_message("[+] Setting fake time...");
+	if (stime(&(time_t){1433512680}) < 0)
+		panic("settimeofday()");
+}
+
 static void mount_filesystems(void)
 {
 	pretty_message("[+] Mounting filesystems...");
@@ -122,12 +123,6 @@ static void enable_logging(void)
 			panic("write(exception-trace)");
 		close(fd);
 	}
-	fd = open("/proc/sys/kernel/panic_on_warn", O_WRONLY);
-	if (fd >= 0) {
-		if (write(fd, "1\n", 2) != 2)
-			panic("write(panic_on_warn)");
-		close(fd);
-	}
 }
 
 static void kmod_selftests(void)
@@ -270,10 +265,11 @@ static void check_leaks(void)
 
 int main(int argc, char *argv[])
 {
-	seed_rng();
 	ensure_console();
 	print_banner();
 	mount_filesystems();
+	seed_rng();
+	set_time();
 	kmod_selftests();
 	enable_logging();
 	clear_leaks();