FAILED: patch "[PATCH] drm/amdgpu/mmhub4.2.0: add bounds checking for cid" failed to apply to 6.18-stable tree

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 9c52f49545478aa47769378cd0b53c5005d6a846
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026032101-polygon-professed-f53c@gregkh' --subject-prefix 'PATCH 6.18.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 9c52f49545478aa47769378cd0b53c5005d6a846 Mon Sep 17 00:00:00 2001
From: Alex Deucher <[email protected]>
Date: Wed, 4 Mar 2026 17:26:17 -0500
Subject: [PATCH] drm/amdgpu/mmhub4.2.0: 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.

index a72770e3d0e9..2532ca80f735 100644
@@ -688,7 +688,8 @@ mmhub_v4_2_0_print_l2_protection_fault_status(struct amdgpu_device *adev,
 		status);
 	switch (amdgpu_ip_version(adev, MMHUB_HWIP, 0)) {
 	case IP_VERSION(4, 2, 0):
-		mmhub_cid = mmhub_client_ids_v4_2_0[cid][rw];
+		mmhub_cid = cid < ARRAY_SIZE(mmhub_client_ids_v4_2_0) ?
+			mmhub_client_ids_v4_2_0[cid][rw] : NULL;
 		break;
 	default:
 		mmhub_cid = NULL;