2 files changed, 89 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/iters.c b/tools/testing/selftests/bpf/progs/iters.c
index 16bdc3e25591..ef70b88bccb2 100644
--- a/tools/testing/selftests/bpf/progs/iters.c
+++ b/tools/testing/selftests/bpf/progs/iters.c
@@ -1432,4 +1432,58 @@ int iter_arr_with_actual_elem_count(const void *ctx)
 	return sum;
 }
 
+__u32 upper, select_n, result;
+__u64 global;
+
+static __noinline bool nest_2(char *str)
+{
+	/* some insns (including branch insns) to ensure stacksafe() is triggered
+	 * in nest_2(). This way, stacksafe() can compare frame associated with nest_1().
+	 */
+	if (str[0] == 't')
+		return true;
+	if (str[1] == 'e')
+		return true;
+	if (str[2] == 's')
+		return true;
+	if (str[3] == 't')
+		return true;
+	return false;
+}
+
+static __noinline bool nest_1(int n)
+{
+	/* case 0: allocate stack, case 1: no allocate stack */
+	switch (n) {
+	case 0: {
+		char comm[16];
+
+		if (bpf_get_current_comm(comm, 16))
+			return false;
+		return nest_2(comm);
+	}
+	case 1:
+		return nest_2((char *)&global);
+	default:
+		return false;
+	}
+}
+
+SEC("raw_tp")
+__success
+int iter_subprog_check_stacksafe(const void *ctx)
+{
+	long i;
+
+	bpf_for(i, 0, upper) {
+		if (!nest_1(select_n)) {
+			result = 1;
+			return 0;
+		}
+	}
+
+	result = 2;
+	return 0;
+}
+
 char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/core/close_range_test.c b/tools/testing/selftests/core/close_range_test.c
index 991c473e3859..12b4eb9d0434 100644
--- a/tools/testing/selftests/core/close_range_test.c
+++ b/tools/testing/selftests/core/close_range_test.c
@@ -589,4 +589,39 @@ TEST(close_range_cloexec_unshare_syzbot)
 	EXPECT_EQ(close(fd3), 0);
 }
 
+TEST(close_range_bitmap_corruption)
+{
+	pid_t pid;
+	int status;
+	struct __clone_args args = {
+		.flags = CLONE_FILES,
+		.exit_signal = SIGCHLD,
+	};
+
+	/* get the first 128 descriptors open */
+	for (int i = 2; i < 128; i++)
+		EXPECT_GE(dup2(0, i), 0);
+
+	/* get descriptor table shared */
+	pid = sys_clone3(&args, sizeof(args));
+	ASSERT_GE(pid, 0);
+
+	if (pid == 0) {
+		/* unshare and truncate descriptor table down to 64 */
+		if (sys_close_range(64, ~0U, CLOSE_RANGE_UNSHARE))
+			exit(EXIT_FAILURE);
+
+		ASSERT_EQ(fcntl(64, F_GETFD), -1);
+		/* ... and verify that the range 64..127 is not
+		   stuck "fully used" according to secondary bitmap */
+		EXPECT_EQ(dup(0), 64)
+			exit(EXIT_FAILURE);
+		exit(EXIT_SUCCESS);
+	}
+
+	EXPECT_EQ(waitpid(pid, &status, 0), pid);
+	EXPECT_EQ(true, WIFEXITED(status));
+	EXPECT_EQ(0, WEXITSTATUS(status));
+}
+
 TEST_HARNESS_MAIN