From ba42b9bf3f193bbc7f47d494bdc888e881539f4b Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Fri, 17 Jan 2025 12:17:08 +0100 Subject: [PATCH 01/23] net: Fix announce_self MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Laurent Vivier RH-MergeRequest: 338: net: Fix announce_self RH-Jira: RHEL-73891 RH-Acked-by: Eugenio Pérez RH-Acked-by: Cindy Lu RH-Commit: [1/1] dfee696c1c444af0ba2b2d3d8c7012385e84885c (lvivier/qemu-kvm-centos) JIRA: https://issues.redhat.com/browse/RHEL-73891 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: Laurent Vivier --- net/net.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/net.c b/net/net.c index fc1125111c..94f51b6e5f 100644 --- a/net/net.c +++ b/net/net.c @@ -828,6 +828,7 @@ 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) { -- 2.48.1