--- wpa_supplicant-2.9/src/utils/os_unix.c.bak	2019-08-07 15:25:25.000000000 +0200
+++ wpa_supplicant-2.9/src/utils/os_unix.c	2021-03-04 12:02:39.637732041 +0100
@@ -10,6 +10,8 @@
 
 #include <time.h>
 #include <sys/wait.h>
+#include <limits.h>
+#include <sys/random.h>
 
 #ifdef ANDROID
 #include <sys/capability.h>
@@ -257,22 +259,30 @@ int os_get_random(unsigned char *buf, si
 		buf[i] = i & 0xff;
 	return 0;
 #else /* TEST_FUZZ */
-	FILE *f;
-	size_t rc;
+	ssize_t written;
+	uint8_t *p = buf;
 
 	if (TEST_FAIL())
 		return -1;
 
-	f = fopen("/dev/urandom", "rb");
-	if (f == NULL) {
-		printf("Could not open /dev/urandom.\n");
-		return -1;
+	if (len > INT_MAX) {
+		fprintf(stderr, "os_get_random: requested %zu bytes\n", len);
+		_exit(1);
 	}
-
-	rc = fread(buf, 1, len, f);
-	fclose(f);
-
-	return rc != len ? -1 : 0;
+	while (len > 0) {
+		do {
+			errno = 0;
+			written = getrandom(p, len, 0);
+		} while ((written == -1) && (errno == EINTR));
+		if (written <= 0) {
+			fprintf(stderr, "os_get_random: getrandom failed: %s\n",
+				strerror(errno));
+			_exit(1);
+		}
+		p += written;
+		len -= written;
+	}
+	return 0;
 #endif /* TEST_FUZZ */
 }