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 8309DC433EF for ; Fri, 1 Jul 2022 14:27:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232365AbiGAO1H (ORCPT ); Fri, 1 Jul 2022 10:27:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231781AbiGAO0K (ORCPT ); Fri, 1 Jul 2022 10:26:10 -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 4472E4579A for ; Fri, 1 Jul 2022 07:24:21 -0700 (PDT) Received: by mail-ed1-x54a.google.com with SMTP id b7-20020a056402350700b00435bd1c4523so1895493edd.5 for ; Fri, 01 Jul 2022 07:24:21 -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=+K29lQHYx/QboL6+Fy2jFmZJqrUMV6q0RSetNFINlHU=; b=Lp2eEEvz0+TgiBntUx4ua/9fGqKccdfR6XH7uHLacnvYo4bPCaLpszQq+8mA0Y5gts YCzUjj3dnLK0eoahSun1hhzXa9zo2wYpNUMZwR4kY7OA35DYyKZ9LQhFeSUbQH6W8LBU cEi1G7HBTkR7zPLvT/TESyx9jjytrH3anjLjFrwMdooDJEmIyePYHuF/VlAGlAiBGHgQ /2HrW5IdeOp02Byommjy5nWcpNJpE2ztvAY4y3tZZGaGC81RVSmcis/j1833duSMcHp5 Z+3w/2IiHJlg4Mg0b3tNbahk09J0jUi+gYRmg2qSYy97kQYMJVderfkH45qNQi5yNzLp 8KnQ== 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=+K29lQHYx/QboL6+Fy2jFmZJqrUMV6q0RSetNFINlHU=; b=xJCL0le2Wzm7yPkshPsKGRIdXfQwqCdCwll/sopBfEZhTDcbFW0zNMPPfFe5PaxCZm CEROAjZNP8R4aeR07FZAHj6nRS9GppEBTbAQZ6DXoUx2n6Sc2BkZcV/fNamzxiDNGN0S UH0+cMiAC+E4oY1vmXg+kSY0lmUDsOrcVhIRq9FQJkxEMZN78RwoR1mvXcsFaoO+tOFr GqaTujKdApc5udQ874dnnWORTPekOASFlewwvTQtATQytBW0Hz5knqbjlgd4Kibr+qEj 099oWIzj81uEurXRDeoOo2PzY9/Klz7wHfyhQKD+PA/ACg32cfW229r0/QsCY8BC3BwA Q5Mw== X-Gm-Message-State: AJIora8EPL51RUaaUT2kKgvKgDIvi9j9794SpUkV2dG9KFQ/EhSIH4Pw ZUEVGVde46YO/B8g6K42fi3RJpqxG90= X-Google-Smtp-Source: AGRyM1v+DIWwLp7Wzl6B8tncc37UxB9rTXYufdTzcwNSGLPhyYz8kU9A/vUtw7VqYleTmtYO9LI0fVniQsI= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:a6f5:f713:759c:abb6]) (user=glider job=sendgmr) by 2002:a05:6402:15a:b0:431:71b9:86f3 with SMTP id s26-20020a056402015a00b0043171b986f3mr18869662edu.249.1656685459864; Fri, 01 Jul 2022 07:24:19 -0700 (PDT) Date: Fri, 1 Jul 2022 16:22:48 +0200 In-Reply-To: <20220701142310.2188015-1-glider@google.com> Message-Id: <20220701142310.2188015-24-glider@google.com> Mime-Version: 1.0 References: <20220701142310.2188015-1-glider@google.com> X-Mailer: git-send-email 2.37.0.rc0.161.g10f37bed90-goog Subject: [PATCH v4 23/45] 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 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-kernel@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 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 13a7348cedfff..2d42a4b38e628 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -329,8 +330,15 @@ 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 -- 2.37.0.rc0.161.g10f37bed90-goog