diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2026-08-11 13:14:40 +0200 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2026-08-11 13:14:40 +0200 |
| commit | 37aae6f352284a07ef69553825aae2fbccc5c4dc (patch) | |
| tree | 66f6cc5e467532e1b03826b2f4db4f36bcbbfd80 | |
| parent | b37971686ec59fb027fa4910ba16805e68fddb97 (diff) | |
| parent | cbb35cbe8db268fefe34c23df15348cf99025298 (diff) | |
Merge branch 'fix-wrong-transport_header-when-sending-vlan-tagged-frames'
Wei Fang says:
====================
Fix wrong transport_header when sending VLAN-tagged frames
When sending a VLAN-tagged frame via AF_PACKET or tap, calling
skb_set_network_header() before skb_probe_transport_header() causes
the flow dissector to misinterpret the inner protocol header as a
VLAN header. As a result, transport_header is never set and remains
at its uninitialized sentinel value (~0U).
Move skb_probe_transport_header() to before skb_set_network_header()
so the flow dissector sees network_header still pointing to the VLAN
header and can correctly identify the transport layer.
====================
Link: https://patch.msgid.link/20260807063405.688780-1-wei.fang@oss.nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | drivers/net/tap.c | 3 | ||||
| -rw-r--r-- | net/packet/af_packet.c | 4 |
2 files changed, 4 insertions, 3 deletions
diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 5d2d34d24ce8..9b5af08cdd47 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -1091,12 +1091,13 @@ static int tap_get_user_xdp(struct tap_queue *q, struct xdp_buff *xdp) } } + skb_probe_transport_header(skb); + /* Move network header to the right position for VLAN tagged packets */ if (eth_type_vlan(skb->protocol) && vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0) skb_set_network_header(skb, depth); - skb_probe_transport_header(skb); dev_queue_xmit(skb); rcu_read_unlock(); diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 435756877aba..213a8a3b7ee5 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1943,13 +1943,13 @@ static void packet_parse_headers(struct sk_buff *skb, struct socket *sock) sock->type == SOCK_RAW) skb->protocol = dev_parse_header_protocol(skb); + skb_probe_transport_header(skb); + /* Move network header to the right position for VLAN tagged packets */ if (likely(skb->dev->type == ARPHRD_ETHER) && eth_type_vlan(skb->protocol) && vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0) skb_set_network_header(skb, depth); - - skb_probe_transport_header(skb); } /* |