1 files changed, 66 insertions, 0 deletions
diff --git a/tools/testing/selftests/exec/recursion-depth.c b/tools/testing/selftests/exec/recursion-depth.c
new file mode 100644
index 000000000000..7b5c4f6d1928
--- /dev/null
+++ b/tools/testing/selftests/exec/recursion-depth.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2019 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test that pointing #! script interpreter to self doesn't recurse. */
+#include <errno.h>
+#include <sched.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/mount.h>
+#include <unistd.h>
+#include "kselftest.h"
+
+int main(void)
+{
+	int fd, rv;
+
+	ksft_print_header();
+	ksft_set_plan(1);
+
+	if (unshare(CLONE_NEWNS) == -1) {
+		if (errno == ENOSYS || errno == EPERM) {
+			ksft_test_result_skip("error: unshare, errno %d\n", errno);
+			ksft_finished();
+		}
+		ksft_exit_fail_perror("error: unshare");
+	}
+
+	if (mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL) == -1)
+		ksft_exit_fail_perror("error: mount '/'");
+
+	/* Require "exec" filesystem. */
+	if (mount(NULL, "/tmp", "ramfs", 0, NULL) == -1)
+		ksft_exit_fail_perror("error: mount ramfs");
+
+#define FILENAME "/tmp/1"
+
+	fd = creat(FILENAME, 0700);
+	if (fd == -1)
+		ksft_exit_fail_perror("error: creat");
+
+#define S "#!" FILENAME "\n"
+	if (write(fd, S, strlen(S)) != strlen(S))
+		ksft_exit_fail_perror("error: write");
+
+	close(fd);
+
+	rv = execve(FILENAME, NULL, NULL);
+	ksft_test_result(rv == -1 && errno == ELOOP,
+			 "execve failed as expected (ret %d, errno %d)\n", rv, errno);
+	ksft_finished();
+}