tests/drm_read: Fix subtest invalid-buffer

Using (void *)-1 directly in read is aborting on chrome systems.
Following message is seen.

Starting subtest: invalid-buffer
*** buffer overflow detected ***: terminated
Received signal SIGABRT.
Stack trace:
Aborted (core dumped)

Patch just adds a pointer variable and uses it in read.

Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Tested-by: Mark Yacoub <markyacoub@chromium.org>
Reviewed-by: Petri Latvala <petri.latvala@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/tests/drm_read.c b/tests/drm_read.c
index ccf9d822..2fdec5be 100644
--- a/tests/drm_read.c
+++ b/tests/drm_read.c
@@ -103,10 +103,11 @@ static void teardown(int fd)
 static void test_invalid_buffer(int in)
 {
 	int fd = setup(in, 0);
+	void *add = (void *)-1;
 
 	alarm(1);
 
-	igt_assert_eq(read(fd, (void *)-1, 4096), -1);
+	igt_assert_eq(read(fd, add, 4096), -1);
 	igt_assert_eq(errno, EFAULT);
 
 	teardown(fd);