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=-9.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 922C9C43467 for ; Thu, 8 Oct 2020 20:43:11 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 F272C21D46 for ; Thu, 8 Oct 2020 20:43:10 +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="XntqAV6R" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F272C21D46 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 7390A2E1BA; Thu, 8 Oct 2020 20:43:10 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id q14rEA3mJ1iY; Thu, 8 Oct 2020 20:43:08 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 1DB512E1B2; Thu, 8 Oct 2020 20:43:08 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 058B5C0893; Thu, 8 Oct 2020 20:43:08 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7702EC0051 for ; Thu, 8 Oct 2020 20:43:07 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 6389387263 for ; Thu, 8 Oct 2020 20:43:07 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 0UOR6KakP5p9 for ; Thu, 8 Oct 2020 20:43:06 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by whitealder.osuosl.org (Postfix) with ESMTPS id C1C4687244 for ; Thu, 8 Oct 2020 20:43:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1602189785; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=huKURS9xZVwjRl6HwVKXLMhhJbFrna5oxeAZtRaNfLM=; b=XntqAV6R1GvrlFkLdDIUC/xMyHYjio6kfZv35RvU8oZm2LQ7ab3J4QTY2VlTAW9a6WKQlr +3jYcB0QSYCA3Q18i9LGBI1tltuO2Mhwg89ZrjXTHBfqRs/LsVdHkNLn6/2fAf6EnbAg+r SB4hJ6oxNm0YJ+n0igiAt+eQh0fgXHE= 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-367-0rDDCUGZOiWINQ_Q48nHTg-1; Thu, 08 Oct 2020 16:43:03 -0400 X-MC-Unique: 0rDDCUGZOiWINQ_Q48nHTg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6B147425EB; Thu, 8 Oct 2020 20:43:02 +0000 (UTC) Received: from steredhat.redhat.com (ovpn-112-116.ams2.redhat.com [10.36.112.116]) by smtp.corp.redhat.com (Postfix) with ESMTP id 556BD55786; Thu, 8 Oct 2020 20:42:57 +0000 (UTC) From: Stefano Garzarella To: mst@redhat.com Subject: [PATCH v2] vringh: fix __vringh_iov() when riov and wiov are different Date: Thu, 8 Oct 2020 22:42:56 +0200 Message-Id: <20201008204256.162292-1-sgarzare@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Cc: kvm@vger.kernel.org, netdev@vger.kernel.org, Rusty Russell , linux-kernel@vger.kernel.org, stable@vger.kernel.org, virtualization@lists.linux-foundation.org X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" If riov and wiov are both defined and they point to different objects, only riov is initialized. If the wiov is not initialized by the caller, the function fails returning -EINVAL and printing "Readable desc 0x... after writable" error message. This issue happens when descriptors have both readable and writable buffers (eg. virtio-blk devices has virtio_blk_outhdr in the readable buffer and status as last byte of writable buffer) and we call __vringh_iov() to get both type of buffers in two different iovecs. Let's replace the 'else if' clause with 'if' to initialize both riov and wiov if they are not NULL. As checkpatch pointed out, we also avoid crashing the kernel when riov and wiov are both NULL, replacing BUG() with WARN_ON() and returning -EINVAL. Fixes: f87d0fbb5798 ("vringh: host-side implementation of virtio rings.") Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella --- drivers/vhost/vringh.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c index e059a9a47cdf..8bd8b403f087 100644 --- a/drivers/vhost/vringh.c +++ b/drivers/vhost/vringh.c @@ -284,13 +284,14 @@ __vringh_iov(struct vringh *vrh, u16 i, desc_max = vrh->vring.num; up_next = -1; + /* You must want something! */ + if (WARN_ON(!riov && !wiov)) + return -EINVAL; + if (riov) riov->i = riov->used = 0; - else if (wiov) + if (wiov) wiov->i = wiov->used = 0; - else - /* You must want something! */ - BUG(); for (;;) { void *addr; -- 2.26.2 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization