drm/amdgpu/mmhub3.0.2: 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.

Reviewed-by: Benjamin Cheng <benjamin.cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1441f52)
Cc: stable@vger.kernel.org

Author: alexdeucher

drivers/gpu/drm/amd/amdgpu/mmhub_v3_0_2.c

@@ -108,7 +108,8 @@ mmhub_v3_0_2_print_l2_protection_fault_status(struct amdgpu_device *adev,
 		"MMVM_L2_PROTECTION_FAULT_STATUS:0x%08X\n",
 		status);
 
-	mmhub_cid = mmhub_client_ids_v3_0_2[cid][rw];
+	mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_v3_0_2) ?
+		mmhub_client_ids_v3_0_2[cid][rw] : NULL;
 	dev_err(adev->dev, "\t Faulty UTCL2 client ID: %s (0x%x)\n",
 		mmhub_cid ? mmhub_cid : "unknown", cid);
 	dev_err(adev->dev, "\t MORE_FAULTS: 0x%lx\n",