[PATCH i-g-t 2/2] tests/intel/xe_compute: check root-only write permission for ccs_mode

[Peter Senna Tschudin <peter.senna@linux.intel.com>]

Add a call to igt_fs_check_root_perm() in test_ccs_mode() to verify that
the "ccs_mode" sysfs attribute is writable only by root. This enforces a
security requirement that only root can modify "ccs_mode", preventing
unintended or unauthorized writes by other users.

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Kamil Konieczny  <kamil.konieczny@linux.intel.com>
Signed-off-by: Peter Senna Tschudin <peter.senna@linux.intel.com>
---
 tests/intel/xe_compute.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tests/intel/xe_compute.c b/tests/intel/xe_compute.c
index 5e9140902..cedcb23d9 100644
--- a/tests/intel/xe_compute.c
+++ b/tests/intel/xe_compute.c
@@ -15,6 +15,7 @@
 
 #include "igt.h"
 #include "igt_sysfs.h"
+#include "igt_fs.h"
 #include "intel_compute.h"
 #include "xe/xe_ioctl.h"
 #include "xe/xe_query.h"
@@ -80,6 +81,12 @@ test_ccs_mode(void)
 
 		num_gt_with_ccs_mode++;
 		gt_fd = gt_sysfs_open(gt);
+
+		/* Check if ccs_mode is writeble only by root. Having root only
+		 * write permission is a security requirement.
+		 */
+		igt_assert(igt_fs_check_root_perm(gt_fd, "ccs_mode"));
+
 		igt_assert(igt_sysfs_printf(gt_fd, "ccs_mode", "%u", 0) < 0);
 		for (m = 1; m <= num_slices; m++) {
 			/* compute slices are to be equally distributed among enabled engines */
-- 
2.43.0