drm/amdgpu/mmhub3.0: 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.

Reviewed-by: Benjamin Cheng <benjamin.cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit f14f27bbe2a3ed7af32d5f6eaf3f417139f45253)
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/amdgpu/mmhub_v3_0.c b/drivers/gpu/drm/amd/amdgpu/mmhub_v3_0.c
index 7d5242df58a511c6b77fc5af1bb1d53d97c481dc..ab966e69a342a30a9f9897b3cc5d0a02c7db522f 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/mmhub_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/mmhub_v3_0.c
@@ -110,7 +110,8 @@ mmhub_v3_0_print_l2_protection_fault_status(struct amdgpu_device *adev,
        switch (amdgpu_ip_version(adev, MMHUB_HWIP, 0)) {
        case IP_VERSION(3, 0, 0):
        case IP_VERSION(3, 0, 1):
-               mmhub_cid = mmhub_client_ids_v3_0_0[cid][rw];
+               mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_v3_0_0) ?
+                       mmhub_client_ids_v3_0_0[cid][rw] : NULL;
                break;
        default:
                mmhub_cid = NULL;