From: Akihiko Odaki Date: Wed, 27 Mar 2024 08:42:56 +0000 (+0900) Subject: hw/net/net_tx_pkt: Fix virtio header without checksum offloading X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=89a8de364b51db8107d2a210314431885ac52238;p=qemu.git hw/net/net_tx_pkt: Fix virtio header without checksum offloading It is incorrect to have the VIRTIO_NET_HDR_F_NEEDS_CSUM set when checksum offloading is disabled so clear the bit. TCP/UDP checksum is usually offloaded when the peer requires virtio headers because they can instruct the peer to compute checksum. However, igb disables TX checksum offloading when a VF is enabled whether the peer requires virtio headers because a transmitted packet can be routed to it and it expects the packet has a proper checksum. Therefore, it is necessary to have a correct virtio header even when checksum offloading is disabled. A real TCP/UDP checksum will be computed and saved in the buffer when checksum offloading is disabled. The virtio specification requires to set the packet checksum stored in the buffer to the TCP/UDP pseudo header when the VIRTIO_NET_HDR_F_NEEDS_CSUM bit is set so the bit must be cleared in that case. Fixes: ffbd2dbd8e64 ("e1000e: Perform software segmentation for loopback") Buglink: https://issues.redhat.com/browse/RHEL-23067 Signed-off-by: Akihiko Odaki Signed-off-by: Jason Wang --- diff --git a/hw/net/net_tx_pkt.c b/hw/net/net_tx_pkt.c index 2e5f58b3c9..2134a18c4c 100644 --- a/hw/net/net_tx_pkt.c +++ b/hw/net/net_tx_pkt.c @@ -833,6 +833,7 @@ bool net_tx_pkt_send_custom(struct NetTxPkt *pkt, bool offload, if (offload || gso_type == VIRTIO_NET_HDR_GSO_NONE) { if (!offload && pkt->virt_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { + pkt->virt_hdr.flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM; net_tx_pkt_do_sw_csum(pkt, &pkt->vec[NET_TX_PKT_L2HDR_FRAG], pkt->payload_frags + NET_TX_PKT_PL_START_FRAG - 1, pkt->payload_len);