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 AD9F8CDB481 for ; Fri, 14 Nov 2025 03:49:01 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vJknW-00043b-Du; Thu, 13 Nov 2025 22:48:30 -0500 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 1vJknU-0003vD-6h for qemu-devel@nongnu.org; Thu, 13 Nov 2025 22:48:28 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vJknQ-0002qF-FN for qemu-devel@nongnu.org; Thu, 13 Nov 2025 22:48:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1763092103; 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=E0uEG2fJ/4Vjdgv1iPVa6yZo48Mgt4U2ZJJ7PuUWSIU=; b=jFOJuF4CZLV3MXRyJZidr7WZDMtCNey5X76qX6OpDNN1BODOyKjdPaRMd4MxCkUs81Xmyu Gz3L4P8n3cGkLXQPnQ9DHvDvBS7oim6iGS+4aYtUofpMssb2d8RgtvoRtlUy5GffuOu3Rq kgho3k/ZGKViXHbqG3kMLao1k8nTGUw= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-402-aP8pUp9uOT6NH7BzXOWMgg-1; Thu, 13 Nov 2025 22:48:21 -0500 X-MC-Unique: aP8pUp9uOT6NH7BzXOWMgg-1 X-Mimecast-MFC-AGG-ID: aP8pUp9uOT6NH7BzXOWMgg_1763092100 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9550D19373D8; Fri, 14 Nov 2025 03:48:20 +0000 (UTC) Received: from localhost.localdomain (unknown [10.72.120.9]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 4330A1800451; Fri, 14 Nov 2025 03:48:15 +0000 (UTC) From: Jason Wang To: qemu-devel@nongnu.org Cc: Jonah Palmer , David Woodhouse , Jason Wang Subject: [PULL 1/5] net/hub: make net_hub_port_cleanup idempotent Date: Fri, 14 Nov 2025 11:48:02 +0800 Message-ID: <20251114034806.2440-2-jasowang@redhat.com> In-Reply-To: <20251114034806.2440-1-jasowang@redhat.com> References: <20251114034806.2440-1-jasowang@redhat.com> MIME-Version: 1.0 Content-type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.133.124; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Jonah Palmer Makes the net_hub_port_cleanup function idempotent to avoid double removals by guarding its QLIST_REMOVE with a flag. When using a Xen networking device with hubport backends, e.g.: -accel kvm,xen-version=0x40011 -netdev hubport,... -device xen-net-device,... the shutdown order starts with net_cleanup, which walks the list and deletes netdevs (including hubports). Then Xen's xen_device_unrealize is called, which eventually leads to a second net_hub_port_cleanup call, resulting in a segfault. Fixes: e7891c57 ("net: move backend cleanup to NIC cleanup") Reported-by: David Woodhouse Signed-off-by: Jonah Palmer Signed-off-by: Jason Wang --- net/hub.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/hub.c b/net/hub.c index e3b58b1c4f..ee5881f6d5 100644 --- a/net/hub.c +++ b/net/hub.c @@ -34,6 +34,7 @@ typedef struct NetHubPort { QLIST_ENTRY(NetHubPort) next; NetHub *hub; int id; + bool listed; } NetHubPort; struct NetHub { @@ -129,7 +130,10 @@ static void net_hub_port_cleanup(NetClientState *nc) { NetHubPort *port = DO_UPCAST(NetHubPort, nc, nc); - QLIST_REMOVE(port, next); + if (port->listed) { + QLIST_REMOVE(port, next); + port->listed = false; + } } static NetClientInfo net_hub_port_info = { @@ -159,8 +163,10 @@ static NetHubPort *net_hub_port_new(NetHub *hub, const char *name, port = DO_UPCAST(NetHubPort, nc, nc); port->id = id; port->hub = hub; + port->listed = false; QLIST_INSERT_HEAD(&hub->ports, port, next); + port->listed = true; return port; } -- 2.42.0