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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 94F18C6FD20 for ; Tue, 21 Mar 2023 21:37:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229852AbjCUVhR (ORCPT ); Tue, 21 Mar 2023 17:37:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229584AbjCUVhQ (ORCPT ); Tue, 21 Mar 2023 17:37:16 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F10256173 for ; Tue, 21 Mar 2023 14:36:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1679434589; 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: in-reply-to:in-reply-to:references:references; bh=2/+8rQXESx0y7iJ/lWjYGgkO51bDoW36uXQ0ZIfOfDY=; b=C8ogjC+BR/ODi5ZE1nvS9+NiIcNstPvCS10S1FSmBNZCJdX1QPUGke8IjRx16yNwuNVP0u L4/6n4kkpTLp4c5SKI7D7Ko9QJB1uFXS0SlZzMEspZsTicGO/JxEMBzo2nPqfzPgiAEsIs j75Qno+nZbUcnVBZzkh3/8DmI2vGL4w= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-177-TJxOIWcnO_OSELqErUGh-Q-1; Tue, 21 Mar 2023 17:36:28 -0400 X-MC-Unique: TJxOIWcnO_OSELqErUGh-Q-1 Received: by mail-wm1-f69.google.com with SMTP id m10-20020a05600c4f4a00b003ed74161838so6830013wmq.6 for ; Tue, 21 Mar 2023 14:36:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679434587; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=2/+8rQXESx0y7iJ/lWjYGgkO51bDoW36uXQ0ZIfOfDY=; b=jaFnVDfyxeK4hy57SWycsQVjjiuBdTI4LX179gQcMXi1AG4q7gSiM/zqsTqnJCHmeg ZloxCbEyggYU0gbpqnkNGmMSOQRnzvSPFXrsbnVNc1QfCxXlMmMSZ0GtlYvuGPkAcsT9 7oeIwzpiZz9GyZBsW1NpJ+h4jHZRa6WnQvo/7SDCXkgVneuLWjRZTwlpMlwW9IqpU5h4 W/1VemfqBp/jcEtTRX/HIGc7MIo0y9QzmNQIoDfHv6LBHxHFy04t1Ml0d9SXBy2pAWWk RkiLw5gyqv/HVSHjQr9VJL4UU/sTV01oA/DAaOw7G1EJOo0S4mIdpJoeVgBZzYfhg85J 1vsA== X-Gm-Message-State: AO0yUKVdFgZK94ZBR5oQKlFTVRNgk3Dya+NVDBNsqTftME6iC13MfVuF aGQKFuvbPb56yWX364a6bHaxM+3Xcr2XXvpcjzema3wTT2ujVWRawxEg6MSjNF1JhIdSpuxb94L Yqm+Vd8BacUXAEP08 X-Received: by 2002:a5d:684a:0:b0:2c7:bb13:e23f with SMTP id o10-20020a5d684a000000b002c7bb13e23fmr3211668wrw.24.1679434587572; Tue, 21 Mar 2023 14:36:27 -0700 (PDT) X-Google-Smtp-Source: AK7set84zvIxrLLTxMQYBkIMEBIwYe7FjxFCYBJQbGyp4XPILZvKxcuzUUAQAoPz/sC15CbsIQ9FYw== X-Received: by 2002:a5d:684a:0:b0:2c7:bb13:e23f with SMTP id o10-20020a5d684a000000b002c7bb13e23fmr3211658wrw.24.1679434587237; Tue, 21 Mar 2023 14:36:27 -0700 (PDT) Received: from redhat.com ([2.52.1.105]) by smtp.gmail.com with ESMTPSA id k16-20020a5d6d50000000b002cff0e213ddsm12180342wri.14.2023.03.21.14.36.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Mar 2023 14:36:26 -0700 (PDT) Date: Tue, 21 Mar 2023 17:36:22 -0400 From: "Michael S. Tsirkin" To: Mike Christie Cc: syzbot , brauner@kernel.org, jasowang@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, virtualization@lists.linux-foundation.org Subject: Re: [syzbot] [kernel?] general protection fault in vhost_task_start Message-ID: <20230321173602-mutt-send-email-mst@kernel.org> References: <0000000000005a60a305f76c07dc@google.com> <2d976892-9914-5de0-62e0-c75f1c148259@oracle.com> <20230321135427-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230321135427-mutt-send-email-mst@kernel.org> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Mar 21, 2023 at 01:55:00PM -0400, Michael S. Tsirkin wrote: > On Tue, Mar 21, 2023 at 12:46:04PM -0500, Mike Christie wrote: > > On 3/21/23 12:03 PM, syzbot wrote: > > > RIP: 0010:vhost_task_start+0x22/0x40 kernel/vhost_task.c:115 > > > Code: 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 53 48 89 fb e8 c3 67 2c 00 48 8d 7b 70 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 0a 48 8b 7b 70 5b e9 fe bd 02 00 e8 79 ec 7e 00 eb > > > RSP: 0018:ffffc90003a9fc38 EFLAGS: 00010207 > > > RAX: dffffc0000000000 RBX: fffffffffffffff4 RCX: 0000000000000000 > > > RDX: 000000000000000c RSI: ffffffff81564c8d RDI: 0000000000000064 > > > RBP: ffff88802b21dd40 R08: 0000000000000100 R09: ffffffff8c917cf3 > > > R10: 00000000fffffff4 R11: 0000000000000000 R12: fffffffffffffff4 > > > R13: ffff888075d000b0 R14: ffff888075d00000 R15: ffff888075d00008 > > > FS: 0000555556247300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > CR2: 00007ffe3d8e5ff8 CR3: 00000000215d4000 CR4: 00000000003506f0 > > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > Call Trace: > > > > > > vhost_worker_create drivers/vhost/vhost.c:580 [inline] > > > > The return value from vhost_task_create is incorrect if the kzalloc fails. > > > > Christian, here is a fix for what's in your tree. Do you want me to submit > > a follow up patch like this or a replacement patch for: > > > > commit 77feab3c4156 ("vhost_task: Allow vhost layer to use copy_process") > > > > with the fix rolled into it? > > > > > > > > > >From 0677ad6d77722f301ca35e8e0f8fd0cbd5ed8484 Mon Sep 17 00:00:00 2001 > > From: Mike Christie > > Date: Tue, 21 Mar 2023 12:39:39 -0500 > > Subject: [PATCH] vhost_task: Fix vhost_task_create return value > > > > vhost_task_create is supposed to return the vhost_task or NULL on > > failure. This fixes it to return the correct value when the allocation > > of the struct fails. > > --- > > kernel/vhost_task.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/kernel/vhost_task.c b/kernel/vhost_task.c > > index 4b8aff160640..b7cbd66f889e 100644 > > --- a/kernel/vhost_task.c > > +++ b/kernel/vhost_task.c > > @@ -88,7 +88,7 @@ struct vhost_task *vhost_task_create(int (*fn)(void *), void *arg, > > > > vtsk = kzalloc(sizeof(*vtsk), GFP_KERNEL); > > if (!vtsk) > > - return ERR_PTR(-ENOMEM); > > + return NULL; > > init_completion(&vtsk->exited); > > vtsk->data = arg; > > vtsk->fn = fn; > > Sorry I had nothing to add here. Sent by mistake.