From patchwork Tue Jun 30 14:57:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Laurent Vivier X-Patchwork-Id: 11634251 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 09341912 for ; Tue, 30 Jun 2020 14:59:06 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id D40B920675 for ; Tue, 30 Jun 2020 14:59:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="JEwKhbxV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D40B920675 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:57838 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jqHiz-0004zt-2y for patchwork-qemu-devel@patchwork.kernel.org; Tue, 30 Jun 2020 10:59:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58940) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jqHho-0002im-GN for qemu-devel@nongnu.org; Tue, 30 Jun 2020 10:57:52 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:59269 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jqHhm-0003FT-Qy for qemu-devel@nongnu.org; Tue, 30 Jun 2020 10:57:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593529070; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GeGjhg9Dw6H0IIKaMoHgzjzja7g8sqMVqZGzBPI60KU=; b=JEwKhbxVToYwU86IuIEnS2V/6WD1vmWbett5gulqhW3STJt3JsIm4J5413vY9VbJXTGY9r ubSqLqkPhMVILe1O2aA+8ggbeBDiGZoXTWl3ZC1u/s2QFVUPqiRT2kgZxqEFlh37GKbpis U08DrkUYTrJuixV8gz2h/I4lKWZoAIw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-196-hyY80WSgMK6UDSkoAKxa2w-1; Tue, 30 Jun 2020 10:57:47 -0400 X-MC-Unique: hyY80WSgMK6UDSkoAKxa2w-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 09A6D107ACF8; Tue, 30 Jun 2020 14:57:46 +0000 (UTC) Received: from thinkpad.redhat.com (ovpn-114-211.ams2.redhat.com [10.36.114.211]) by smtp.corp.redhat.com (Postfix) with ESMTP id 02464741A6; Tue, 30 Jun 2020 14:57:43 +0000 (UTC) From: Laurent Vivier To: qemu-devel@nongnu.org Subject: [PATCH v2 1/2] net: tap: check if the file descriptor is valid before using it Date: Tue, 30 Jun 2020 16:57:36 +0200 Message-Id: <20200630145737.232095-2-lvivier@redhat.com> In-Reply-To: <20200630145737.232095-1-lvivier@redhat.com> References: <20200630145737.232095-1-lvivier@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=lvivier@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.61; envelope-from=lvivier@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/30 01:11:03 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Stefan Weil , Jason Wang , Markus Armbruster , Gerd Hoffmann , Paolo Bonzini , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" qemu_set_nonblock() checks that the file descriptor can be used and, if not, crashes QEMU. An assert() is used for that. The use of assert() is used to detect programming error and the coredump will allow to debug the problem. But in the case of the tap device, this assert() can be triggered by a misconfiguration by the user. At startup, it's not a real problem, but it can also happen during the hot-plug of a new device, and here it's a problem because we can crash a perfectly healthy system. For instance: # ip link add link virbr0 name macvtap0 type macvtap mode bridge # ip link set macvtap0 up # TAP=/dev/tap$(ip -o link show macvtap0 | cut -d: -f1) # qemu-system-x86_64 -machine q35 -device pcie-root-port,id=pcie-root-port-0 -monitor stdio 9<> $TAP (qemu) netdev_add type=tap,id=hostnet0,vhost=on,fd=9 (qemu) device_add driver=virtio-net-pci,netdev=hostnet0,id=net0,bus=pcie-root-port-0 (qemu) device_del net0 (qemu) netdev_del hostnet0 (qemu) netdev_add type=tap,id=hostnet1,vhost=on,fd=9 qemu-system-x86_64: .../util/oslib-posix.c:247: qemu_set_nonblock: Assertion `f != -1' failed. Aborted (core dumped) To avoid that, check the file descriptor is valid before passing it to qemu_set_non_block() for "fd=" and "fds=" parameters. Signed-off-by: Laurent Vivier Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Greg Kurz --- include/qemu/sockets.h | 1 + net/tap.c | 13 +++++++++++++ util/oslib-posix.c | 5 +++++ util/oslib-win32.c | 6 ++++++ 4 files changed, 25 insertions(+) diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h index 57cd049d6edd..5b0c2d77ddad 100644 --- a/include/qemu/sockets.h +++ b/include/qemu/sockets.h @@ -17,6 +17,7 @@ int qemu_socket(int domain, int type, int protocol); int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen); int socket_set_cork(int fd, int v); int socket_set_nodelay(int fd); +bool qemu_fd_is_valid(int fd); void qemu_set_block(int fd); void qemu_set_nonblock(int fd); int socket_set_fast_reuse(int fd); diff --git a/net/tap.c b/net/tap.c index 6207f61f84ab..f65966aaccd8 100644 --- a/net/tap.c +++ b/net/tap.c @@ -795,6 +795,12 @@ int net_init_tap(const Netdev *netdev, const char *name, return -1; } + /* Check if fd is valid */ + if (!qemu_fd_is_valid(fd)) { + error_setg(errp, "Invalid file descriptor %d", fd); + return -1; + } + qemu_set_nonblock(fd); vnet_hdr = tap_probe_vnet_hdr(fd); @@ -843,6 +849,13 @@ int net_init_tap(const Netdev *netdev, const char *name, goto free_fail; } + /* Check if fd is valid */ + if (!qemu_fd_is_valid(fd)) { + error_setg(errp, "Invalid file descriptor %d", fd); + ret = -1; + goto free_fail; + } + qemu_set_nonblock(fd); if (i == 0) { diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 916f1be2243a..8d5705f598d3 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -244,6 +244,11 @@ void qemu_anon_ram_free(void *ptr, size_t size) qemu_ram_munmap(-1, ptr, size); } +bool qemu_fd_is_valid(int fd) +{ + return fcntl(fd, F_GETFL) != -1; +} + void qemu_set_block(int fd) { int f; diff --git a/util/oslib-win32.c b/util/oslib-win32.c index e9b14ab17847..a6be9445cfdb 100644 --- a/util/oslib-win32.c +++ b/util/oslib-win32.c @@ -132,6 +132,12 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) } #endif /* CONFIG_LOCALTIME_R */ +bool qemu_fd_is_valid(int fd) +{ + /* FIXME: how to check if fd is valid? */ + return true; +} + void qemu_set_block(int fd) { unsigned long opt = 0; From patchwork Tue Jun 30 14:57:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Vivier X-Patchwork-Id: 11634255 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BF858912 for ; Tue, 30 Jun 2020 14:59:59 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 9554120675 for ; Tue, 30 Jun 2020 14:59:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hNSh4Dvq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9554120675 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:32824 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jqHjq-0006H8-PF for patchwork-qemu-devel@patchwork.kernel.org; Tue, 30 Jun 2020 10:59:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58962) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jqHhu-0002zO-EO for qemu-devel@nongnu.org; Tue, 30 Jun 2020 10:57:58 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:32523 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jqHho-0003Fd-I6 for qemu-devel@nongnu.org; Tue, 30 Jun 2020 10:57:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593529071; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=20NAFHynPx9DjQRXiLXqEjvBYe5DS2rwSVpuGZzTeKE=; b=hNSh4Dvqo5UQlEmYGgTYdsjfukfiCkyeUQschh86fS49V1Zeb5KtmY3xcnt9K4jpjNEof6 NJXTYt+DRxTmlMacoGMhwpSzJPbb3GOv65qgh0grsrJRMmQA9Cxz44wlXyBAat9J5tQWP6 9dNb2RHss4WgnQmMFgGlH3pIM2gPp+s= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-261-KRE0-6eGO1CM5cWN0VoFkA-1; Tue, 30 Jun 2020 10:57:49 -0400 X-MC-Unique: KRE0-6eGO1CM5cWN0VoFkA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 92A7F6BF97; Tue, 30 Jun 2020 14:57:48 +0000 (UTC) Received: from thinkpad.redhat.com (ovpn-114-211.ams2.redhat.com [10.36.114.211]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5D126741B5; Tue, 30 Jun 2020 14:57:46 +0000 (UTC) From: Laurent Vivier To: qemu-devel@nongnu.org Subject: [PATCH v2 2/2] net: detect errors from probing vnet hdr flag for TAP devices Date: Tue, 30 Jun 2020 16:57:37 +0200 Message-Id: <20200630145737.232095-3-lvivier@redhat.com> In-Reply-To: <20200630145737.232095-1-lvivier@redhat.com> References: <20200630145737.232095-1-lvivier@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=lvivier@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.81; envelope-from=lvivier@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/30 02:00:02 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Stefan Weil , Jason Wang , Markus Armbruster , "Dr . David Alan Gilbert" , Gerd Hoffmann , Paolo Bonzini , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: "Daniel P. Berrange" When QEMU sets up a tap based network device backend, it mostly ignores errors reported from various ioctl() calls it makes, assuming the TAP file descriptor is valid. This assumption can easily be violated when the user is passing in a pre-opened file descriptor. At best, the ioctls may fail with a -EBADF, but if the user passes in a bogus FD number that happens to clash with a FD number that QEMU has opened internally for another reason, a wide variety of errnos may result, as the TUNGETIFF ioctl number may map to a completely different command on a different type of file. By ignoring all these errors, QEMU sets up a zombie network backend that will never pass any data. Even worse, when QEMU shuts down, or that network backend is hot-removed, it will close this bogus file descriptor, which could belong to another QEMU device backend. There's no obvious guaranteed reliable way to detect that a FD genuinely is a TAP device, as opposed to a UNIX socket, or pipe, or something else. Checking the errno from probing vnet hdr flag though, does catch the big common cases. ie calling TUNGETIFF will return EBADF for an invalid FD, and ENOTTY when FD is a UNIX socket, or pipe which catches accidental collisions with FDs used for stdio, or monitor socket. Previously the example below where bogus fd 9 collides with the FD used for the chardev saw: $ ./x86_64-softmmu/qemu-system-x86_64 -netdev tap,id=hostnet0,fd=9 \ -chardev socket,id=charchannel0,path=/tmp/qga,server,nowait \ -monitor stdio -vnc :0 qemu-system-x86_64: -netdev tap,id=hostnet0,fd=9: TUNGETIFF ioctl() failed: Inappropriate ioctl for device TUNSETOFFLOAD ioctl() failed: Bad address QEMU 2.9.1 monitor - type 'help' for more information (qemu) Warning: netdev hostnet0 has no peer which gives a running QEMU with a zombie network backend. With this change applied we get an error message and QEMU immediately exits before carrying on and making a bigger disaster: $ ./x86_64-softmmu/qemu-system-x86_64 -netdev tap,id=hostnet0,fd=9 \ -chardev socket,id=charchannel0,path=/tmp/qga,server,nowait \ -monitor stdio -vnc :0 qemu-system-x86_64: -netdev tap,id=hostnet0,vhost=on,fd=9: Unable to query TUNGETIFF on FD 9: Inappropriate ioctl for device Reported-by: Dr. David Alan Gilbert Signed-off-by: Daniel P. Berrange Tested-by: Dr. David Alan Gilbert Message-id: 20171027085548.3472-1-berrange@redhat.com [lv: to simplify, don't check on EINVAL with TUNGETIFF as it exists since v2.6.27] Signed-off-by: Laurent Vivier --- net/tap-bsd.c | 2 +- net/tap-linux.c | 8 +++++--- net/tap-solaris.c | 2 +- net/tap-stub.c | 2 +- net/tap.c | 25 ++++++++++++++++++++----- net/tap_int.h | 2 +- 6 files changed, 29 insertions(+), 12 deletions(-) diff --git a/net/tap-bsd.c b/net/tap-bsd.c index a5c3707f806d..77aaf674b19d 100644 --- a/net/tap-bsd.c +++ b/net/tap-bsd.c @@ -211,7 +211,7 @@ void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp) { } -int tap_probe_vnet_hdr(int fd) +int tap_probe_vnet_hdr(int fd, Error **errp) { return 0; } diff --git a/net/tap-linux.c b/net/tap-linux.c index e0dd442ee34f..b0635e9e32ce 100644 --- a/net/tap-linux.c +++ b/net/tap-linux.c @@ -147,13 +147,15 @@ void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp) } } -int tap_probe_vnet_hdr(int fd) +int tap_probe_vnet_hdr(int fd, Error **errp) { struct ifreq ifr; if (ioctl(fd, TUNGETIFF, &ifr) != 0) { - error_report("TUNGETIFF ioctl() failed: %s", strerror(errno)); - return 0; + /* TUNGETIFF is available since kernel v2.6.27 */ + error_setg_errno(errp, errno, + "Unable to query TUNGETIFF on FD %d", fd); + return -1; } return ifr.ifr_flags & IFF_VNET_HDR; diff --git a/net/tap-solaris.c b/net/tap-solaris.c index 4725d2314eef..ae2ba6828415 100644 --- a/net/tap-solaris.c +++ b/net/tap-solaris.c @@ -206,7 +206,7 @@ void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp) { } -int tap_probe_vnet_hdr(int fd) +int tap_probe_vnet_hdr(int fd, Error **errp) { return 0; } diff --git a/net/tap-stub.c b/net/tap-stub.c index a9ab8f829362..de525a2e69d4 100644 --- a/net/tap-stub.c +++ b/net/tap-stub.c @@ -37,7 +37,7 @@ void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp) { } -int tap_probe_vnet_hdr(int fd) +int tap_probe_vnet_hdr(int fd, Error **errp) { return 0; } diff --git a/net/tap.c b/net/tap.c index f65966aaccd8..f0ba0ae069cb 100644 --- a/net/tap.c +++ b/net/tap.c @@ -597,7 +597,11 @@ int net_init_bridge(const Netdev *netdev, const char *name, } qemu_set_nonblock(fd); - vnet_hdr = tap_probe_vnet_hdr(fd); + vnet_hdr = tap_probe_vnet_hdr(fd, errp); + if (vnet_hdr < 0) { + close(fd); + return -1; + } s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr); snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper, @@ -803,7 +807,11 @@ int net_init_tap(const Netdev *netdev, const char *name, qemu_set_nonblock(fd); - vnet_hdr = tap_probe_vnet_hdr(fd); + vnet_hdr = tap_probe_vnet_hdr(fd, errp); + if (vnet_hdr < 0) { + close(fd); + return -1; + } net_init_tap_one(tap, peer, "tap", name, NULL, script, downscript, @@ -859,8 +867,11 @@ int net_init_tap(const Netdev *netdev, const char *name, qemu_set_nonblock(fd); if (i == 0) { - vnet_hdr = tap_probe_vnet_hdr(fd); - } else if (vnet_hdr != tap_probe_vnet_hdr(fd)) { + vnet_hdr = tap_probe_vnet_hdr(fd, errp); + if (vnet_hdr < 0) { + goto free_fail; + } + } else if (vnet_hdr != tap_probe_vnet_hdr(fd, NULL)) { error_setg(errp, "vnet_hdr not consistent across given tap fds"); ret = -1; @@ -905,7 +916,11 @@ free_fail: } qemu_set_nonblock(fd); - vnet_hdr = tap_probe_vnet_hdr(fd); + vnet_hdr = tap_probe_vnet_hdr(fd, errp); + if (vnet_hdr < 0) { + close(fd); + return -1; + } net_init_tap_one(tap, peer, "bridge", name, ifname, script, downscript, vhostfdname, diff --git a/net/tap_int.h b/net/tap_int.h index e3194b23f47d..225a49ea4843 100644 --- a/net/tap_int.h +++ b/net/tap_int.h @@ -34,7 +34,7 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr, ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen); void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp); -int tap_probe_vnet_hdr(int fd); +int tap_probe_vnet_hdr(int fd, Error **errp); int tap_probe_vnet_hdr_len(int fd, int len); int tap_probe_has_ufo(int fd); void tap_fd_set_offload(int fd, int csum, int tso4, int tso6, int ecn, int ufo);