[PATCH v2 2/6] selftests/clone3: add a check for invalid exit_signal

[Eugene Syromiatnikov]

Check that the kernel fails calls with exit_signal with non-zero highest
32 bits, negative 32-bit exit_signal, and not failing on passing
invalid exit_signal withing CSIGNAL mask, like legacy clone syscalls do.

* tools/testing/selftests/clone3/clone3.c (enum test_mode): Add
CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,
CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG.
(call_clone3): Add args.exit_signal initialisation in case test_mode
is equal to one of the added enum test_mode values.
(main): Add test_clone3 clone check with test_mode equal to the added
enum test_mode values.

Signed-off-by: Eugene Syromiatnikov <esyr@xxxxxxxxxx>
---
 tools/testing/selftests/clone3/clone3.c | 36 +++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/tools/testing/selftests/clone3/clone3.c b/tools/testing/selftests/clone3/clone3.c
index 7b65ee5..318189f9 100644
--- a/tools/testing/selftests/clone3/clone3.c
+++ b/tools/testing/selftests/clone3/clone3.c
@@ -28,6 +28,10 @@ enum test_mode {
 	CLONE3_ARGS_NO_TEST,
 	CLONE3_ARGS_ALL_0,
 	CLONE3_ARGS_ALL_1,
+	CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG,
+	CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,
+	CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG,
+	CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG,
 };
 
 static pid_t raw_clone(struct clone_args *args, size_t size)
@@ -72,6 +76,22 @@ static int call_clone3(int flags, size_t size, enum test_mode test_mode)
 		args.tls = 1;
 		args.set_tid = 1;
 		break;
+
+	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG:
+		args.exit_signal = 0xbadc0ded00000000ULL;
+		break;
+
+	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG:
+		args.exit_signal = 0x0000000080000000ULL;
+		break;
+
+	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG:
+		args.exit_signal = 0x0000000000000100ULL;
+		break;
+
+	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG:
+		args.exit_signal = 0x00000000000000f0ULL;
+		break;
 	}
 
 	pid = raw_clone(&args, size);
@@ -146,6 +166,22 @@ int main(int argc, char *argv[])
 	/* Do a clone3() with all members set to 1 */
 	if (test_clone3(0, CLONE3_ARGS_SIZE_V0, -EINVAL, CLONE3_ARGS_ALL_1))
 		goto on_error;
+	/* Do a clone3() with exit_signal having highest 32 bits non-zero */
+	if (test_clone3(0, CLONE3_ARGS_SIZE_V0, -EINVAL,
+			CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG))
+		goto on_error;
+	/* Do a clone3() with negative 32-bit exit_signal */
+	if (test_clone3(0, CLONE3_ARGS_SIZE_V0, -EINVAL,
+			CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG))
+		goto on_error;
+	/* Do a clone3() with exit_signal not fitting into CSIGNAL mask */
+	if (test_clone3(0, CLONE3_ARGS_SIZE_V0, -EINVAL,
+			CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG))
+		goto on_error;
+	/* Do a clone3() with NSIG < exit_signal < CSIG */
+	if (test_clone3(0, CLONE3_ARGS_SIZE_V0, 0,
+			CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG))
+		goto on_error;
 	/*
 	 * Do a clone3() with sizeof(struct clone_args) + 8
 	 * and all members set to 0.
-- 
2.1.4