[PATCH net 2/2] octeon_ep_vf: fix skb frags overflow in the RX path
From: Maoyi Xie <hidden>
Date: 2026-07-01 11:28:39
Also in:
lkml
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
__octep_vf_oq_process_rx() has the same unbounded fragment loop as the PF
driver. buff_info->len comes from the device response header, and one
fragment is added per buffer_size chunk with no check against
MAX_SKB_FRAGS. A long packet yields about 18 fragments, one past 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. It drains the descriptors the same way the build_skb failure
path does.
Fixes: 1cd3b407977c ("octeon_ep_vf: add Tx/Rx processing and interrupt support")
Co-developed-by: Kaixuan Li <redacted>
Signed-off-by: Kaixuan Li <redacted>
Signed-off-by: Maoyi Xie <redacted>
---
.../ethernet/marvell/octeon_ep_vf/octep_vf_rx.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_rx.c b/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_rx.c
index d982474082423..2e666df26b4c3 100644
--- a/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_rx.c
+++ b/drivers/net/ethernet/marvell/octeon_ep_vf/octep_vf_rx.c@@ -463,6 +463,23 @@ static int __octep_vf_oq_process_rx(struct octep_vf_device *oct, 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); + while (data_len) { + dma_unmap_page(oq->dev, oq->desc_ring[read_idx].buffer_ptr, + PAGE_SIZE, DMA_FROM_DEVICE); + buff_info = (struct octep_vf_rx_buffer *) + &oq->buff_info[read_idx]; + buff_info->page = NULL; + if (data_len < oq->buffer_size) + data_len = 0; + else + data_len -= oq->buffer_size; + desc_used++; + read_idx = octep_vf_oq_next_idx(oq, read_idx); + } + continue; + } while (data_len) { dma_unmap_page(oq->dev, oq->desc_ring[read_idx].buffer_ptr, PAGE_SIZE, DMA_FROM_DEVICE);
--
2.34.1