selftests/memfd/memfd_test: fix possible NULL pointer dereference

If `name' is NULL, a NULL pointer may be accessed in printf.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: liuye <[email protected]>
Reviewed-by: Lorenzo Stoakes <[email protected]>
Cc: Greg Thelen <[email protected]>
Cc: "Isaac J. Manjarres" <[email protected]>
Cc: Jeff Xu <[email protected]>
Cc: Saurav Shah <[email protected]>
Cc: Shuah Khan (Samsung OSG) <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: qiyeliu

tools/testing/selftests/memfd/memfd_test.c

@@ -171,7 +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();
 	}