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 72593C433EF for ; Mon, 29 Nov 2021 18:29:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379410AbhK2SdG (ORCPT ); Mon, 29 Nov 2021 13:33:06 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:35732 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379224AbhK2SbD (ORCPT ); Mon, 29 Nov 2021 13:31:03 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id BB907B815D2; Mon, 29 Nov 2021 18:27:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2C6CC53FC7; Mon, 29 Nov 2021 18:27:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638210463; bh=xLEXFZDlt93SawD6InGVDuoCHOOS/eIZKQ5fge2jGQI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1cz+nkfZQH+wUzszY6bwNJutbklbKmyFSUGc5KsSmH7NjOwheZuMc75G9oVP4961y /TfpwIFcpScLRMQfmRKynyxX8OjnmVcoZQNv8wTauxco6qQL6v/SYXzkx+xWJKaK6E PGkWC+CCrlKY4KeEtutINNPyrFZdD6yhgv/2Grbs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Halil Pasic , Jason Wang , Stefano Garzarella , "Michael S. Tsirkin" , Stefan Hajnoczi Subject: [PATCH 5.4 78/92] vhost/vsock: fix incorrect used length reported to the guest Date: Mon, 29 Nov 2021 19:18:47 +0100 Message-Id: <20211129181710.008958085@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211129181707.392764191@linuxfoundation.org> References: <20211129181707.392764191@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: linux-kernel@vger.kernel.org From: Stefano Garzarella commit 49d8c5ffad07ca014cfae72a1b9b8c52b6ad9cb8 upstream. The "used length" reported by calling vhost_add_used() must be the number of bytes written by the device (using "in" buffers). In vhost_vsock_handle_tx_kick() the device only reads the guest buffers (they are all "out" buffers), without writing anything, so we must pass 0 as "used length" to comply virtio spec. Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko") Cc: stable@vger.kernel.org Reported-by: Halil Pasic Suggested-by: Jason Wang Signed-off-by: Stefano Garzarella Link: https://lore.kernel.org/r/20211122163525.294024-2-sgarzare@redhat.com Signed-off-by: Michael S. Tsirkin Reviewed-by: Stefan Hajnoczi Reviewed-by: Halil Pasic Signed-off-by: Greg Kroah-Hartman --- drivers/vhost/vsock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -491,7 +491,7 @@ static void vhost_vsock_handle_tx_kick(s virtio_transport_free_pkt(pkt); len += sizeof(pkt->hdr); - vhost_add_used(vq, head, len); + vhost_add_used(vq, head, 0); total_len += len; added = true; } while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));