drm/amdgpu/gmc9.0: add bounds checking for cid

The value should never exceed the array size as those
are the only values the hardware is expected to return,
but add checks anyway.

Cc: Benjamin Cheng <benjamin.cheng@amd.com>
Reviewed-by: Benjamin Cheng <benjamin.cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit e14d468)
Cc: stable@vger.kernel.org

Author: alexdeucher

drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c

@@ -662,28 +662,35 @@ static int gmc_v9_0_process_interrupt(struct amdgpu_device *adev,
 	} else {
 		switch (amdgpu_ip_version(adev, MMHUB_HWIP, 0)) {
 		case IP_VERSION(9, 0, 0):
-			mmhub_cid = mmhub_client_ids_vega10[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_vega10) ?
+				mmhub_client_ids_vega10[cid][rw] : NULL;
 			break;
 		case IP_VERSION(9, 3, 0):
-			mmhub_cid = mmhub_client_ids_vega12[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_vega12) ?
+				mmhub_client_ids_vega12[cid][rw] : NULL;
 			break;
 		case IP_VERSION(9, 4, 0):
-			mmhub_cid = mmhub_client_ids_vega20[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_vega20) ?
+				mmhub_client_ids_vega20[cid][rw] : NULL;
 			break;
 		case IP_VERSION(9, 4, 1):
-			mmhub_cid = mmhub_client_ids_arcturus[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_arcturus) ?
+				mmhub_client_ids_arcturus[cid][rw] : NULL;
 			break;
 		case IP_VERSION(9, 1, 0):
 		case IP_VERSION(9, 2, 0):
-			mmhub_cid = mmhub_client_ids_raven[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_raven) ?
+				mmhub_client_ids_raven[cid][rw] : NULL;
 			break;
 		case IP_VERSION(1, 5, 0):
 		case IP_VERSION(2, 4, 0):
-			mmhub_cid = mmhub_client_ids_renoir[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_renoir) ?
+				mmhub_client_ids_renoir[cid][rw] : NULL;
 			break;
 		case IP_VERSION(1, 8, 0):
 		case IP_VERSION(9, 4, 2):
-			mmhub_cid = mmhub_client_ids_aldebaran[cid][rw];
+			mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_aldebaran) ?
+				mmhub_client_ids_aldebaran[cid][rw] : NULL;
 			break;
 		default:
 			mmhub_cid = NULL;