net: xilinx: axienet: Add error handling for RX metadata pointer retrieval

Add proper error checking for dmaengine_desc_get_metadata_ptr() which
can return an error pointer and lead to potential crashes or undefined
behaviour if the pointer retrieval fails.

Properly handle the error by unmapping DMA buffer, freeing the skb and
returning early to prevent further processing with invalid data.

Fixes: 6a91b846af ("net: axienet: Introduce dmaengine support")
Signed-off-by: Abin Joseph <abin.joseph@amd.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://patch.msgid.link/20250903025213.3120181-1-abin.joseph@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Abin Joseph 2025-09-03 08:22:13 +05:30 committed by Jakub Kicinski
parent d93b10e894
commit 8bbceba7dc
1 changed files with 10 additions and 0 deletions

View File

@ -1168,6 +1168,15 @@ static void axienet_dma_rx_cb(void *data, const struct dmaengine_result *result)
&meta_max_len);
dma_unmap_single(lp->dev, skbuf_dma->dma_address, lp->max_frm_size,
DMA_FROM_DEVICE);
if (IS_ERR(app_metadata)) {
if (net_ratelimit())
netdev_err(lp->ndev, "Failed to get RX metadata pointer\n");
dev_kfree_skb_any(skb);
lp->ndev->stats.rx_dropped++;
goto rx_submit;
}
/* TODO: Derive app word index programmatically */
rx_len = (app_metadata[LEN_APP] & 0xFFFF);
skb_put(skb, rx_len);
@ -1180,6 +1189,7 @@ static void axienet_dma_rx_cb(void *data, const struct dmaengine_result *result)
u64_stats_add(&lp->rx_bytes, rx_len);
u64_stats_update_end(&lp->rx_stat_sync);
rx_submit:
for (i = 0; i < CIRC_SPACE(lp->rx_ring_head, lp->rx_ring_tail,
RX_BUF_NUM_DEFAULT); i++)
axienet_rx_submit_desc(lp->ndev);