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 2AA98ECAAA1 for ; Thu, 15 Sep 2022 15:08:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231132AbiIOPIv (ORCPT ); Thu, 15 Sep 2022 11:08:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230376AbiIOPHP (ORCPT ); Thu, 15 Sep 2022 11:07:15 -0400 Received: from mail-ed1-x54a.google.com (mail-ed1-x54a.google.com [IPv6:2a00:1450:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 364779677E for ; Thu, 15 Sep 2022 08:05:40 -0700 (PDT) Received: by mail-ed1-x54a.google.com with SMTP id x5-20020a05640226c500b00451ec193793so8530382edd.16 for ; Thu, 15 Sep 2022 08:05:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=lOWe2UvDp+lzLw75WkGUXRoANIiWBb139LkOr44Ytus=; b=r8zwtK7nR6FXPBS442hkgib03/UyNe7gNUiweombLjUeUOwj8SF20sAORY+JgIxfJC xdQzkfFn7/UIZp6qs2BkVURbVTIpmVyq4CogUpIZzqnkOvB4czCVAsUxHuaXyYzg7wYj iSHZbV2gUMNZdtwTkVyP2zImSyDUIobXdqb3vW/gaStenqfHXMWXmhtPDGK7i0t2+x+V LX9ocp5gmEP0hXd6aLkG4expCb4w3nGprape1+X4fjnbTnlSElSS0OcneVvlkPCu1k1v zulBsEXPwjPW//HgEDA7XFR0M2WbDQmJA13wrulrEaaWrxCq8Z7S8FbCgch7VF6L5ax7 LfJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=lOWe2UvDp+lzLw75WkGUXRoANIiWBb139LkOr44Ytus=; b=tKySQdqh5JFcaCYqJBfoVMHD9R7r6+PFg5aSa8Cz6b+YXHNLgVMWfoJtmyQ+gCTr1I 6DRHYb0/LN340THu80f1d1eRdR8m0ljOJBRqX7rSSjUT04kEUIegAz0aVHw02xDLUqb+ RHwobQX/LvfWIppo3zc0cWSmOEDhDq0VFtONwIWNVeDqVr5rYrzIEWPXYPtCdps4FKIv RArVOO1Z7GSqvvsTv3wZ642/rZp8p19EL8SF8RAVFBC7be3PvxY9Ps8h7iPwYDBCtotV SQx/WTe3eqI94Om1IIyRyzvo+a9zO6gmYXJFG7pYOCIP/jGnMeGO/fnd9boJRYYr9P+q PC/A== X-Gm-Message-State: ACrzQf34XrlveXP5hGgW1GGfb7M/+lXAAVLLmAsShq0dLXeJMl6ip8tv QIjqXiz5wTTGY/ncR63XGHEqWathTDw= X-Google-Smtp-Source: AMsMyM6XUfiL29ncKe/ZK/EpTsQsoLddOpxaN22/2HU0VmNdXXQuif+Od6cd/SXFxh2r6j465cljcQVOjxc= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:686d:27b5:495:85b7]) (user=glider job=sendgmr) by 2002:a17:906:58c8:b0:6fe:91d5:18d2 with SMTP id e8-20020a17090658c800b006fe91d518d2mr326676ejs.190.1663254338524; Thu, 15 Sep 2022 08:05:38 -0700 (PDT) Date: Thu, 15 Sep 2022 17:03:56 +0200 In-Reply-To: <20220915150417.722975-1-glider@google.com> Mime-Version: 1.0 References: <20220915150417.722975-1-glider@google.com> X-Mailer: git-send-email 2.37.2.789.g6183377224-goog Message-ID: <20220915150417.722975-23-glider@google.com> Subject: [PATCH v7 22/43] virtio: kmsan: check/unpoison scatterlist in vring_map_one_sg() From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Alexei Starovoitov , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Biggers , 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 , Stephen Rothwell , 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 --- v4: -- swap virtio: and kmsan: in the subject v6: -- use instead of 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 4620e9d79dde8..8974c34b40fda 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -352,8 +353,15 @@ 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 -- 2.37.2.789.g6183377224-goog