From: Laurent Vivier Date: Fri, 17 Jan 2025 11:17:08 +0000 (+0100) Subject: net: Fix announce_self X-Git-Tag: v9.1.3~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=01d03bafcd0f6a66e1abb59696afd2fb3ee81d27;p=thirdparty%2Fqemu.git net: Fix announce_self b9ad513e1876 ("net: Remove receive_raw()") adds an iovec entry in qemu_deliver_packet_iov() to add the virtio-net header in the data when QEMU_NET_PACKET_FLAG_RAW is set but forgets to increase the number of iovec entries in the array, so receive_iov() will only send the first entry (the virtio-net entry, full of 0) and no data. The packet will be discarded. The only user of QEMU_NET_PACKET_FLAG_RAW is announce_self. We can see the problem with tcpdump: - QEMU parameters: .. -monitor stdio \ -netdev bridge,id=netdev0,br=virbr0 \ -device virtio-net,mac=9a:2b:2c:2d:2e:2f,netdev=netdev0 \ - HMP command: (qemu) announce_self - TCP dump: $ sudo tcpdump -nxi virbr0 without the fix: with the fix: ARP, Reverse Request who-is 9a:2b:2c:2d:2e:2f tell 9a:2b:2c:2d:2e:2f, length 46 0x0000: 0001 0800 0604 0003 9a2b 2c2d 2e2f 0000 0x0010: 0000 9a2b 2c2d 2e2f 0000 0000 0000 0000 0x0020: 0000 0000 0000 0000 0000 0000 0000 Reported-by: Xiaohui Li Bug: https://issues.redhat.com/browse/RHEL-73891 Fixes: b9ad513e1876 ("net: Remove receive_raw()") Cc: akihiko.odaki@daynix.com Signed-off-by: Laurent Vivier Reviewed-by: Akihiko Odaki Reviewed-by: Michael Tokarev Signed-off-by: Michael Tokarev (cherry picked from commit 84dfdcbff33fff185528501be408c25c44499f32) Signed-off-by: Michael Tokarev --- diff --git a/net/net.c b/net/net.c index 264c4e9c5c..39ef1fb43d 100644 --- a/net/net.c +++ b/net/net.c @@ -832,6 +832,7 @@ static ssize_t qemu_deliver_packet_iov(NetClientState *sender, iov_copy[0].iov_len = nc->vnet_hdr_len; memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov)); iov = iov_copy; + iovcnt++; } if (nc->info->receive_iov) {