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 X-Spam-Level: X-Spam-Status: No, score=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33316C433E3 for ; Mon, 22 Mar 2021 12:39:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 07C9A619AF for ; Mon, 22 Mar 2021 12:39:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231751AbhCVMio (ORCPT ); Mon, 22 Mar 2021 08:38:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:56922 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231915AbhCVMhJ (ORCPT ); Mon, 22 Mar 2021 08:37:09 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F10A4619B0; Mon, 22 Mar 2021 12:36:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1616416594; bh=O4s0c9JoysGQ5mVTheWhFvVgaK+FQc/o3HURvt+AD8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G0Xy3uHO0Oyo3OIeFvYX9enN7sFxOQZWf+LYlFitZ+lb+PQOnHgngPDuzpF7HbtoF PZnM65ZobxM74K18mXv+y26lz+J5Vjgo6giv7l8JOhW6hnPNymVL6EpJ/Sz2EN3V2k Bx9i9gyb+5w6BVOc9ynHEplQz+QWQY0Yqf1KvAww= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gautam Dawar , Jason Wang , "Michael S. Tsirkin" Subject: [PATCH 5.10 047/157] vhost_vdpa: fix the missing irq_bypass_unregister_producer() invocation Date: Mon, 22 Mar 2021 13:26:44 +0100 Message-Id: <20210322121935.241064318@linuxfoundation.org> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210322121933.746237845@linuxfoundation.org> References: <20210322121933.746237845@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Gautam Dawar commit 4c050286bb202cffd5467c1cba982dff391d62e1 upstream. When qemu with vhost-vdpa netdevice is run for the first time, it works well. But after the VM is powered off, the next qemu run causes kernel panic due to a NULL pointer dereference in irq_bypass_register_producer(). When the VM is powered off, vhost_vdpa_clean_irq() misses on calling irq_bypass_unregister_producer() for irq 0 because of the existing check. This leaves stale producer nodes, which are reset in vhost_vring_call_reset() when vhost_dev_init() is invoked during the second qemu run. As the node member of struct irq_bypass_producer is also initialized to zero, traversal on the producers list causes crash due to NULL pointer dereference. Fixes: 2cf1ba9a4d15c ("vhost_vdpa: implement IRQ offloading in vhost_vdpa") Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211711 Signed-off-by: Gautam Dawar Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210224114845.104173-1-gdawar.xilinx@gmail.com Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman --- drivers/vhost/vdpa.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -910,14 +910,10 @@ err: static void vhost_vdpa_clean_irq(struct vhost_vdpa *v) { - struct vhost_virtqueue *vq; int i; - for (i = 0; i < v->nvqs; i++) { - vq = &v->vqs[i]; - if (vq->call_ctx.producer.irq) - irq_bypass_unregister_producer(&vq->call_ctx.producer); - } + for (i = 0; i < v->nvqs; i++) + vhost_vdpa_unsetup_vq_irq(v, i); } static int vhost_vdpa_release(struct inode *inode, struct file *filep)