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 72BD6C433F5 for ; Tue, 14 Dec 2021 16:24:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236052AbhLNQYX (ORCPT ); Tue, 14 Dec 2021 11:24:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236034AbhLNQXq (ORCPT ); Tue, 14 Dec 2021 11:23:46 -0500 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 5228BC061751 for ; Tue, 14 Dec 2021 08:23:33 -0800 (PST) Received: by mail-ed1-x54a.google.com with SMTP id p4-20020aa7d304000000b003e7ef120a37so17384560edq.16 for ; Tue, 14 Dec 2021 08:23:33 -0800 (PST) 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=AQV6gal7xcYqVzVr1Fdti0Xi6wxVWlKKmnc0dLEZLM8=; b=b3jhMZ+gtnb0jZdcbymOiOH3N4uF7ztLrqbNz30Lv2gY/fV9Ysm768H49DQ8/xsqDs 3IWlVkODvwaD+EJvZuTNbktU0WaOOSZHUsqp8QqkiwCjohzFOu6txRL7zkE4px1LcdIk vxd5HuCl389N3V8vVv47QaEENGeKSAVUqrG28FVdb0SAZssc5+xj0XeyIIN9bKbyM+on Am44ePDuKhmUb7BWyplo6vc0OeMhMfMyxIOC81WBZkpDw1pLZir5v7e7d0vLqnwzMew6 hA5cisSZnjkJnZUIjDxzZR8BgPbTDD1a4PpQeqFA5R4A95BYLgdHW8cBeaznDvAgDZQB ASxA== 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=AQV6gal7xcYqVzVr1Fdti0Xi6wxVWlKKmnc0dLEZLM8=; b=yp7+DE0M9Bbs6pw+MzSp5Fv7sr9grhAPEB+m7s5Il8IDq4jt+QVlvrFtoRB9XkvHES l3edrS8gKXv4eFZQvZZpyUNBtMgLGlrFDCG13aWBqcaX2GwKmKFEOHEQs142YukHA9Lf o66QFgbx1wzPdsW9MeaIFucNisZlshPIejUe/ayZVl3U86hJl8c6s9IEBvipnQQ8eMBI Cub1y4ZiGlzKBMyJug7Tx1p+/s/SjksUXT2+OAH4nvynfidbzVZ8dEg53gh2lq7XoLBE Mxtk17zuA8r9EIVDayuXPoIEMlgVcybUiKl2tO0VdSyTZ2LT5DFm7FnVjqIBNZNlZ24H nIoQ== X-Gm-Message-State: AOAM532miDP6rEGOT/tSAu8xRJOg4RCH5+mFG/128ZOLSjmUoIzvXSPx 1Opd4PacdVK1MsG50IgnYvYt1c97Aso= X-Google-Smtp-Source: ABdhPJwLPasgbm+76JeLxEcgZP9XNbaJpFUP/XX1HfS3uh/8mkJSzHomfuQTgR60DvU3f9qWQoPIPwmcbts= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:357e:2b9d:5b13:a652]) (user=glider job=sendgmr) by 2002:a17:906:cd17:: with SMTP id oz23mr866387ejb.415.1639499011704; Tue, 14 Dec 2021 08:23:31 -0800 (PST) Date: Tue, 14 Dec 2021 17:20:43 +0100 In-Reply-To: <20211214162050.660953-1-glider@google.com> Message-Id: <20211214162050.660953-37-glider@google.com> Mime-Version: 1.0 References: <20211214162050.660953-1-glider@google.com> X-Mailer: git-send-email 2.34.1.173.g76aa8bc2d0-goog Subject: [PATCH 36/43] x86: kmsan: sync metadata pages on page fault From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Ard Biesheuvel , 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 , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , 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 KMSAN assumes shadow and origin pages for every allocated page are accessible. For pages between [VMALLOC_START, VMALLOC_END] those metadata pages start at KMSAN_VMALLOC_SHADOW_START and KMSAN_VMALLOC_ORIGIN_START, therefore we must sync a bigger memory region. Signed-off-by: Alexander Potapenko --- Link: https://linux-review.googlesource.com/id/Ia5bd541e54f1ecc11b86666c3ec87c62ac0bdfb8 --- arch/x86/mm/fault.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 4bfed53e210ec..abed0aedf00d2 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -260,7 +260,7 @@ static noinline int vmalloc_fault(unsigned long address) } NOKPROBE_SYMBOL(vmalloc_fault); -void arch_sync_kernel_mappings(unsigned long start, unsigned long end) +void __arch_sync_kernel_mappings(unsigned long start, unsigned long end) { unsigned long addr; @@ -284,6 +284,26 @@ void arch_sync_kernel_mappings(unsigned long start, unsigned long end) } } +void arch_sync_kernel_mappings(unsigned long start, unsigned long end) +{ + __arch_sync_kernel_mappings(start, end); + /* + * KMSAN maintains two additional metadata page mappings for the + * [VMALLOC_START, VMALLOC_END) range. These mappings start at + * KMSAN_VMALLOC_SHADOW_START and KMSAN_VMALLOC_ORIGIN_START and + * have to be synced together with the vmalloc memory mapping. + */ + if (IS_ENABLED(CONFIG_KMSAN) && + start >= VMALLOC_START && end < VMALLOC_END) { + __arch_sync_kernel_mappings( + start - VMALLOC_START + KMSAN_VMALLOC_SHADOW_START, + end - VMALLOC_START + KMSAN_VMALLOC_SHADOW_START); + __arch_sync_kernel_mappings( + start - VMALLOC_START + KMSAN_VMALLOC_ORIGIN_START, + end - VMALLOC_START + KMSAN_VMALLOC_ORIGIN_START); + } +} + static bool low_pfn(unsigned long pfn) { return pfn < max_low_pfn; -- 2.34.1.173.g76aa8bc2d0-goog