__octep_oq_process_rx() builds an skb for a multi-buffer packet by adding one fragment per buffer_size chunk: data_len = buff_info->len - oq->max_single_buffer_size; while (data_len) { ... skb_add_rx_frag(skb, shinfo->nr_frags, buff_info->page, 0, buff_info->len, buff_info->len); ... } buff_info->len comes from the device response header (be64_to_cpu(resp_hw->length)). Nothing bounds the fragment count against MAX_SKB_FRAGS. data_len can be close to 65535. buffer_size defaults to about 3776 on 4K pages, so a full packet yields about 18 fragments. That is one more than the default MAX_SKB_FRAGS of 17, so skb_add_rx_frag() writes past shinfo->frags[]. The driver now drops a packet that would need more fragments than the skb can hold. octep_oq_drop_rx() consumes its descriptors, as on the build_skb failure path. The same class was fixed in other RX paths, including commit 5ffcb7b890f6 ("net: atlantic: fix fragment overflow handling in RX path") and commit f0813bcd2d9d ("net: wwan: t7xx: fix potential skb->frags overflow in RX path"). Fixes: 37d79d059606 ("octeon_ep: add Tx/Rx processing and interrupt support") Co-developed-by: Kaixuan Li Signed-off-by: Kaixuan Li Signed-off-by: Maoyi Xie --- drivers/net/ethernet/marvell/octeon_ep/octep_rx.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c b/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c index e6ebc7e44a00c..4ee911b6c0107 100644 --- a/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c +++ b/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c @@ -476,6 +476,12 @@ static int __octep_oq_process_rx(struct octep_device *oct, skb_put(skb, oq->max_single_buffer_size); shinfo = skb_shinfo(skb); data_len = buff_info->len - oq->max_single_buffer_size; + if (DIV_ROUND_UP(data_len, oq->buffer_size) > MAX_SKB_FRAGS) { + dev_kfree_skb_any(skb); + octep_oq_drop_rx(oq, buff_info, + &read_idx, &desc_used); + continue; + } while (data_len) { buff_info = (struct octep_rx_buffer *) &oq->buff_info[read_idx]; -- 2.34.1