FAILED: patch "[PATCH] i40e: add validation for ring_len param" failed to apply to 5.4-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.4-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 <stable@vger.kernel.org>.

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-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 55d225670def06b01af2e7a5e0446fbe946289e8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025092936-anvil-pummel-9e58@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

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

From 55d225670def06b01af2e7a5e0446fbe946289e8 Mon Sep 17 00:00:00 2001
From: Lukasz Czapnik <lukasz.czapnik@intel.com>
Date: Wed, 13 Aug 2025 12:45:11 +0200
Subject: [PATCH] i40e: add validation for ring_len param

The `ring_len` parameter provided by the virtual function (VF)
is assigned directly to the hardware memory context (HMC) without
any validation.

To address this, introduce an upper boundary check for both Tx and Rx
queue lengths. The maximum number of descriptors supported by the
hardware is 8k-32.
Additionally, enforce alignment constraints: Tx rings must be a multiple
of 8, and Rx rings must be a multiple of 32.

Fixes: 5c3c48ac6bf5 ("i40e: implement virtual device interface")
Cc: stable@vger.kernel.org
Signed-off-by: Lukasz Czapnik <lukasz.czapnik@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index 9b8efdeafbcf..cb37b2ac56f1 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -653,6 +653,13 @@ static int i40e_config_vsi_tx_queue(struct i40e_vf *vf, u16 vsi_id,
 
 	/* only set the required fields */
 	tx_ctx.base = info->dma_ring_addr / 128;
+
+	/* ring_len has to be multiple of 8 */
+	if (!IS_ALIGNED(info->ring_len, 8) ||
+	    info->ring_len > I40E_MAX_NUM_DESCRIPTORS_XL710) {
+		ret = -EINVAL;
+		goto error_context;
+	}
 	tx_ctx.qlen = info->ring_len;
 	tx_ctx.rdylist = le16_to_cpu(vsi->info.qs_handle[0]);
 	tx_ctx.rdylist_act = 0;
@@ -716,6 +723,13 @@ static int i40e_config_vsi_rx_queue(struct i40e_vf *vf, u16 vsi_id,
 
 	/* only set the required fields */
 	rx_ctx.base = info->dma_ring_addr / 128;
+
+	/* ring_len has to be multiple of 32 */
+	if (!IS_ALIGNED(info->ring_len, 32) ||
+	    info->ring_len > I40E_MAX_NUM_DESCRIPTORS_XL710) {
+		ret = -EINVAL;
+		goto error_param;
+	}
 	rx_ctx.qlen = info->ring_len;
 
 	if (info->splithdr_enabled) {