6.17-stable review patch. If anyone has any objections, please let me know.
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From: Mohammad Heib mheib@redhat.com
[ Upstream commit de0337d641bfa5b6d6b489e479792f1039274e84 ]
The TSO path called ionic_tx_map_skb() before preparing the TCP pseudo checksum (ionic_tx_tcp_[inner_]pseudo_csum()), which may perform skb_cow_head() and might modifies bytes in the linear header area.
Mapping first and then mutating the header risks: - Using a stale DMA address if skb_cow_head() relocates the head, and/or - Device reading stale header bytes on weakly-ordered systems (CPU writes after mapping are not guaranteed visible without an explicit dma_sync_single_for_device()).
Reorder the TX path to perform all header mutations (including skb_cow_head()) *before* DMA mapping. Mapping is now done only after the skb layout and header contents are final. This removes the need for any post-mapping dma_sync and prevents on-wire corruption observed under VLAN+TSO load after repeated runs.
This change is purely an ordering fix; no functional behavior change otherwise.
Fixes: 0f3154e6bcb3 ("ionic: Add Tx and Rx handling") Signed-off-by: Mohammad Heib mheib@redhat.com Reviewed-by: Brett Creeley brett.creeley@amd.com Link: https://patch.msgid.link/20251031155203.203031-2-mheib@redhat.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/pensando/ionic/ionic_txrx.c | 30 ++++++++----------- 1 file changed, 13 insertions(+), 17 deletions(-)
diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c index 2e571d0a0d8a2..301ebee2fdc50 100644 --- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c +++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c @@ -1448,19 +1448,6 @@ static int ionic_tx_tso(struct net_device *netdev, struct ionic_queue *q, bool encap; int err;
- desc_info = &q->tx_info[q->head_idx]; - - if (unlikely(ionic_tx_map_skb(q, skb, desc_info))) - return -EIO; - - len = skb->len; - mss = skb_shinfo(skb)->gso_size; - outer_csum = (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE | - SKB_GSO_GRE_CSUM | - SKB_GSO_IPXIP4 | - SKB_GSO_IPXIP6 | - SKB_GSO_UDP_TUNNEL | - SKB_GSO_UDP_TUNNEL_CSUM)); has_vlan = !!skb_vlan_tag_present(skb); vlan_tci = skb_vlan_tag_get(skb); encap = skb->encapsulation; @@ -1474,12 +1461,21 @@ static int ionic_tx_tso(struct net_device *netdev, struct ionic_queue *q, err = ionic_tx_tcp_inner_pseudo_csum(skb); else err = ionic_tx_tcp_pseudo_csum(skb); - if (unlikely(err)) { - /* clean up mapping from ionic_tx_map_skb */ - ionic_tx_desc_unmap_bufs(q, desc_info); + if (unlikely(err)) return err; - }
+ desc_info = &q->tx_info[q->head_idx]; + if (unlikely(ionic_tx_map_skb(q, skb, desc_info))) + return -EIO; + + len = skb->len; + mss = skb_shinfo(skb)->gso_size; + outer_csum = (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE | + SKB_GSO_GRE_CSUM | + SKB_GSO_IPXIP4 | + SKB_GSO_IPXIP6 | + SKB_GSO_UDP_TUNNEL | + SKB_GSO_UDP_TUNNEL_CSUM)); if (encap) hdrlen = skb_inner_tcp_all_headers(skb); else