Restore old umask after creating file.

lib/util_mosq.c

@@ -404,9 +404,17 @@ FILE *_mosquitto_fopen(const char *path, const char *mode, bool restrict_read)
 	}
 #else
 	if (restrict_read) {
-		umask(0700);
+		FILE *fptr;
+		mode_t old_mask;
+
+		old_mask = umask(0700);
+		fptr = fopen(path, mode);
+		umask(old_mask);
+
+		return fptr;
+	}else{
+		return fopen(path, mode);
 	}
-	return fopen(path, mode);
 #endif
 }