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 41950C433FE for ; Tue, 26 Apr 2022 16:47:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353276AbiDZQvB (ORCPT ); Tue, 26 Apr 2022 12:51:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353305AbiDZQtL (ORCPT ); Tue, 26 Apr 2022 12:49:11 -0400 Received: from mail-ed1-x549.google.com (mail-ed1-x549.google.com [IPv6:2a00:1450:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C9413D4BD for ; Tue, 26 Apr 2022 09:45:27 -0700 (PDT) Received: by mail-ed1-x549.google.com with SMTP id n4-20020a5099c4000000b00418ed58d92fso10618114edb.0 for ; Tue, 26 Apr 2022 09:45:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=n12oscJoQy25ZeJEgKUppRaHioaFclURl8PsqxmYCmo=; b=PIyBhpOCM8Ov1/+Aan+YSMRBfpf54pHX8ytL+CV9/1wxPrduFClfDo2MC25BFRGqUr LC5Hr2Ef8nJt4G1Cr30fbnTHYjTJ5Gax8GaKjFXG0iL+r/c29mApiZT+RSwu1Gv2kkOz 34uVLpDsIsKTbG2q42gMn4a9Vr9GOVlaxiLfXa8b/4pWebY6TjT2x9JFCSEXRuOPPg3n b/OGc6pwoUP/SU7+PJ629KnVXCQHZctVc5m6qyPQPfIcXk7XKqS9AYp6qyxiblVFksU/ vePEsS5V3b8GJxiZEtgsjh4z7hZSSCwDY93JM9PnMnCLZhZrlsTx6bFvrt7KV12fLlqe re3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=n12oscJoQy25ZeJEgKUppRaHioaFclURl8PsqxmYCmo=; b=BfjcXfvMzZmDUZ7VLTYIlNZQN10OX1OKvRTJvMCocwXexnpaJ3tQWrvlISnfuWujP+ Zwsqi3e2XFsR9VEIx3VQUFXfEoiBQi+dMmX3nMys38KXI/Py07xxqqjRSH2O4+14D1Yu 4Sjc9fYveubVMI5530JtZx9DgjORVLU2XEPhS2cHzOiPIm8pVfMgG1cQ+KhUmwHbuvst zvrh+/nljj6KsttSdELDwTxckHBL7SCzUcd21ZXraRPBEhsnxWk/sWg6Nk7UgUQc+gWE sYZXt/rafOdIKJ+Gj484ddGQyhniHlGDhbZ+VO7cJxUkW7thJTkkhFqoWxp/VEgRj7Gw iTKA== X-Gm-Message-State: AOAM530T4lRTkVS50pGcmHj5IxZTLlaEPklhc7OHSuL23pHvi3iFUWmI N8jC4T0rIwbuLQt7k4P30paV+3b8pWI= X-Google-Smtp-Source: ABdhPJxU8JwPhcVfaOXEOS2U2ep3mvLwmmcZHEz36qAom9R3kEeJAH/9Z6s5Sw7k1Wv/sYn9qCbZoM2w78E= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:d580:abeb:bf6d:5726]) (user=glider job=sendgmr) by 2002:a05:6402:5210:b0:423:de77:2a4d with SMTP id s16-20020a056402521000b00423de772a4dmr25186177edd.295.1650991525861; Tue, 26 Apr 2022 09:45:25 -0700 (PDT) Date: Tue, 26 Apr 2022 18:42:54 +0200 In-Reply-To: <20220426164315.625149-1-glider@google.com> Message-Id: <20220426164315.625149-26-glider@google.com> Mime-Version: 1.0 References: <20220426164315.625149-1-glider@google.com> X-Mailer: git-send-email 2.36.0.rc2.479.g8af0fa9b8e-goog Subject: [PATCH v3 25/46] kmsan: virtio: check/unpoison scatterlist in vring_map_one_sg() From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org If vring doesn't use the DMA API, KMSAN is unable to tell whether the memory is initialized by hardware. Explicitly call kmsan_handle_dma() from vring_map_one_sg() in this case to prevent false positives. Signed-off-by: Alexander Potapenko Acked-by: Michael S. Tsirkin --- Link: https://linux-review.googlesource.com/id/I211533ecb86a66624e151551f83ddd749536b3af --- drivers/virtio/virtio_ring.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index cfb028ca238eb..faecd9e3d6560 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -331,8 +332,15 @@ static dma_addr_t vring_map_one_sg(const struct vring_virtqueue *vq, struct scatterlist *sg, enum dma_data_direction direction) { - if (!vq->use_dma_api) + if (!vq->use_dma_api) { + /* + * If DMA is not used, KMSAN doesn't know that the scatterlist + * is initialized by the hardware. Explicitly check/unpoison it + * depending on the direction. + */ + kmsan_handle_dma(sg_page(sg), sg->offset, sg->length, direction); return (dma_addr_t)sg_phys(sg); + } /* * We can't use dma_map_sg, because we don't use scatterlists in -- 2.36.0.rc2.479.g8af0fa9b8e-goog