Commit b809d040 authored by Aditya Garg's avatar Aditya Garg Committed by Jakub Kicinski
Browse files

net: mana: validate rx_req_idx to prevent out-of-bounds array access 



In mana_hwc_rx_event_handler(), rx_req_idx is derived from
sge->address in DMA-coherent memory. In Confidential VMs
(SEV-SNP/TDX), this memory is shared unencrypted and HW can modify
WQE contents at any time. No bounds check exists on rx_req_idx,
which can lead to an out-of-bounds access into reqs[].

Add bounds check on rx_req_idx in mana_hwc_rx_event_handler() before
using it to index the reqs[] array.

Fixes: ca9c54d2 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)")
Signed-off-by: default avatarAditya Garg <gargaditya@linux.microsoft.com>
Reviewed-by: default avatarHaiyang Zhang <haiyangz@microsoft.com>
Link: https://patch.msgid.link/20260520051553.857120-1-gargaditya@linux.microsoft.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 9eddc819

drivers/net/ethernet/microsoft/mana/hw_channel.c

+6 −0
Original line number Diff line number Diff line
@@ -265,6 +265,12 @@ static void mana_hwc_rx_event_handler(void *ctx, u32 gdma_rxq_id, 
	rq_base_addr = hwc_rxq->msg_buf->mem_info.dma_handle;

	rx_req_idx = (sge->address - rq_base_addr) / hwc->max_req_msg_size;



	if (rx_req_idx >= hwc_rxq->msg_buf->num_reqs) {

		dev_err(hwc->dev, "HWC RX: wrong rx_req_idx=%llu, num_reqs=%u\n",

			rx_req_idx, hwc_rxq->msg_buf->num_reqs);

		return;

	}



	rx_req = &hwc_rxq->msg_buf->reqs[rx_req_idx];

	resp = (struct gdma_resp_hdr *)rx_req->buf_va;