From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B0C5FC77B78 for ; Wed, 3 May 2023 11:04:12 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1puAGb-0006Eq-9v; Wed, 03 May 2023 07:03:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1puAGZ-0006EP-KT for qemu-devel@nongnu.org; Wed, 03 May 2023 07:03:23 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1puAGX-00085w-6l for qemu-devel@nongnu.org; Wed, 03 May 2023 07:03:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683111799; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=VJadEu+6zRBnoWcF+9JpYQ3UZe7sRKE2r/xUzyXg8pY=; b=arGaYaFM66DLq6e80jgY4NKs6mGwPTtUIyzLnvoRhczpY7Smb5+kZLko5uiz7oAzqRG11j pkb8x09A/eJLymRD71jND5Fj9aJ0GD+a8NjZgxevLkG4Qxpy1E8KW9QLMHtt6SBxDNAUMJ Ir+TBl3heU/YqzXb72eTiHZGd17xZgg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-561-e6lLQcXuO-uOW1zZ5cNc1A-1; Wed, 03 May 2023 07:03:16 -0400 X-MC-Unique: e6lLQcXuO-uOW1zZ5cNc1A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id F312929ABA18; Wed, 3 May 2023 11:03:15 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.37]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B13301121331; Wed, 3 May 2023 11:03:14 +0000 (UTC) Date: Wed, 3 May 2023 12:03:12 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Andrew Melnychenko Cc: jasowang@redhat.com, mst@redhat.com, armbru@redhat.com, eblake@redhat.com, qemu-devel@nongnu.org, yuri.benditovich@daynix.com, yan@daynix.com Subject: Re: [PATCH 2/5] virtio-net: Added property to load eBPF RSS with fds. Message-ID: References: <20230501072101.22890-1-andrew@daynix.com> <20230501072101.22890-3-andrew@daynix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230501072101.22890-3-andrew@daynix.com> User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.161, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, May 01, 2023 at 10:20:58AM +0300, Andrew Melnychenko wrote: > eBPF RSS program and maps may now be passed during initialization. > Initially was implemented for libvirt to launch qemu without permissions, > and initialized eBPF program through the helper. > > Signed-off-by: Andrew Melnychenko > --- > hw/net/virtio-net.c | 96 +++++++++++++++++++++++++++++++--- > include/hw/virtio/virtio-net.h | 1 + > 2 files changed, 91 insertions(+), 6 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 53e1c326433..9b3a997d872 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -42,6 +42,7 @@ > #include "sysemu/sysemu.h" > #include "trace.h" > #include "monitor/qdev.h" > +#include "monitor/monitor.h" > #include "hw/pci/pci_device.h" > #include "net_rx_pkt.h" > #include "hw/virtio/vhost.h" > @@ -1305,14 +1306,96 @@ static void virtio_net_detach_epbf_rss(VirtIONet *n) > virtio_net_attach_ebpf_to_backend(n->nic, -1); > } > > -static bool virtio_net_load_ebpf(VirtIONet *n) > +static int virtio_net_get_ebpf_rss_fds(char *str, char *fds[], int nfds, > + Error **errp) > { > - if (!virtio_net_attach_ebpf_to_backend(n->nic, -1)) { > - /* backend does't support steering ebpf */ > - return false; > + char *ptr = str; > + char *cur = NULL; > + size_t len = strlen(str); > + int i = 0; > + > + for (; i < nfds && ptr < str + len;) { > + cur = strchr(ptr, ':'); > + > + if (cur == NULL) { > + fds[i] = g_strdup(ptr); > + } else { > + fds[i] = g_strndup(ptr, cur - ptr); > + } > + > + i++; > + if (cur == NULL) { > + break; > + } else { > + ptr = cur + 1; > + } > + } > + > + if (cur != NULL) { > + /* the string contains more arguments */ > + error_setg(errp, > + "Too many eBPF file descriptors for RSS provided."); > + } else if (i < nfds) { > + error_setg(errp, > + "Not enough eBPF file descriptors for RSS were provided."); > + } > + > + return i; > +} This whole method could be replaced by a call to g_strsplit in the caller.... > + > +static bool virtio_net_load_ebpf_fds(VirtIONet *n, Error **errp) > +{ > + char *fds_strs[EBPF_RSS_MAX_FDS]; g_autoptr(GStrv) fds_strs = g_strsplit(n->ebpf_rss_fds, ",", 0); > + int fds[EBPF_RSS_MAX_FDS]; Left as uninitialized stack memory. > + int nfds; > + int ret = true; > + int i = 0; > + > + ERRP_GUARD(); > + > + nfds = virtio_net_get_ebpf_rss_fds(n->ebpf_rss_fds, > + fds_strs, EBPF_RSS_MAX_FDS, errp); > + if (*errp) { > + ret = false; > + goto exit; > } Replace with if (g_strv_length(fds_strs) != EBPF_RSS_MAX_FDS) { error_setg(errp, "Expected %d file descriptors but got %d", EBPF_RSS_MAX_FDS, g_strv_length(fds_strs)); return false; } > > - return ebpf_rss_load(&n->ebpf_rss); > + for (i = 0; i < nfds; i++) { > + fds[i] = monitor_fd_param(monitor_cur(), fds_strs[i], errp); > + if (*errp) { > + ret = false; > + goto exit; This can break out of the loop before all elements in 'fds' are initialized. > + } > + } > + > + ret = ebpf_rss_load_fds(&n->ebpf_rss, fds[0], fds[1], fds[2], fds[3]); > + > +exit: > + if (!ret || *errp) { > + for (i = 0; i < nfds; i++) { > + close(fds[i]); > + } > + } This now calls close() on uninitialized memory, killing arbitary FDs QEMU has open elsewhere. > + > + for (i = 0; i < nfds; i++) { > + g_free(fds_strs[i]); > + } Not required if we use g_autoptr(GStrv) > + > + return ret; > +} > + > +static bool virtio_net_load_ebpf(VirtIONet *n, Error **errp) > +{ > + bool ret = false; > + > + if (virtio_net_attach_ebpf_to_backend(n->nic, -1)) { > + if (!(n->ebpf_rss_fds > + && virtio_net_load_ebpf_fds(n, errp))) { > + ret = ebpf_rss_load(&n->ebpf_rss); > + } > + } > + > + return ret; > } > > static void virtio_net_unload_ebpf(VirtIONet *n) > @@ -3738,7 +3821,7 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > net_rx_pkt_init(&n->rx_pkt); > > if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) { > - virtio_net_load_ebpf(n); > + virtio_net_load_ebpf(n, errp); > } > } > > @@ -3900,6 +3983,7 @@ static Property virtio_net_properties[] = { > VIRTIO_NET_F_RSS, false), > DEFINE_PROP_BIT64("hash", VirtIONet, host_features, > VIRTIO_NET_F_HASH_REPORT, false), > + DEFINE_PROP_STRING("ebpf_rss_fds", VirtIONet, ebpf_rss_fds), > DEFINE_PROP_BIT64("guest_rsc_ext", VirtIONet, host_features, > VIRTIO_NET_F_RSC_EXT, false), > DEFINE_PROP_UINT32("rsc_interval", VirtIONet, rsc_timeout, > diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h > index ef234ffe7ef..e10ce88f918 100644 > --- a/include/hw/virtio/virtio-net.h > +++ b/include/hw/virtio/virtio-net.h > @@ -219,6 +219,7 @@ struct VirtIONet { > VirtioNetRssData rss_data; > struct NetRxPkt *rx_pkt; > struct EBPFRSSContext ebpf_rss; > + char *ebpf_rss_fds; > }; > > size_t virtio_net_handle_ctrl_iov(VirtIODevice *vdev, > -- > 2.39.1 > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|