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 2CF06C433EF for ; Tue, 26 Apr 2022 16:49:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345607AbiDZQwG (ORCPT ); Tue, 26 Apr 2022 12:52:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353368AbiDZQvB (ORCPT ); Tue, 26 Apr 2022 12:51:01 -0400 Received: from mail-ej1-x64a.google.com (mail-ej1-x64a.google.com [IPv6:2a00:1450:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1CA11483A7 for ; Tue, 26 Apr 2022 09:46:11 -0700 (PDT) Received: by mail-ej1-x64a.google.com with SMTP id hp17-20020a1709073e1100b006ef69a535c3so9361546ejc.10 for ; Tue, 26 Apr 2022 09:46:11 -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=SGOwGjYq/2PwacKh0/9At0yFevcHrzg9FDlShmi+vnk=; b=fSZ4zfvDJJmqaIzU1XL0WfStwXr6OPa8V+ga0qTz0UlsIHyG9I6Fr6ZEbs9vmLiuhO ClbMCWmC+tznTOah7YoL3txE0BplWerCcj5Pt/KeycPvVB+sF+pTOE13LG7aV8CaSZd6 CtB276fuSEgHwCIg/10uWG7rSCD98aAcUKoO+LU4U8ks8bUI5/GdxxpoNac4ZhTkb0E1 grtFS0KyEl74V0H8NCr4jzX10gmxpamQ+wZyHKObaL9HWxab3p+XWx1x2TN57EUQX6a4 MV6fXbcDTcGpFO2Dt7YM5K3PDMZSDsLSt5fDbOOZGvHfv6pU1T6bZgqLE57A40M5bQwM 0uLw== 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=SGOwGjYq/2PwacKh0/9At0yFevcHrzg9FDlShmi+vnk=; b=pbwXyN7tnReibsJKqwWs52IdzKC83Dxm8jxPAadEOgdnDffY2RwgUXZaTZhGqby4yN /jBrj4u6nGC983Gz83EFUZLIryUJpUsKnApXUOv6yeXPkvrD6L+FYvbOWpGFRVhAjLHl c8YVIHshObi7zHcYwx8WYWbZTtNe5HFIBO+U0Rg7RDptm7AZWCHXxsZtONW7LXhKnZ/O indwk2WIIofKI4YXRNRpMMx/DRTTBJ6cudzR7fQqatol5udFBxiQJxg89f3dMmdZ0Ilr /SABi3wZghp8318AGpv+cb8ilXlYSFeLx1RDxO1oNu5DhfasVyCFAmB8LZcMJBEOlJ9/ s0RQ== X-Gm-Message-State: AOAM531nSPw5BC7xWpFhS0so7NCJqOt8fLrtYyzJ35PDHozz6cUtdfnB 1QV3P0TmVXlucFY8rKDjyhvBsxT0dlo= X-Google-Smtp-Source: ABdhPJw9NptsR6xC76SX+4t0lKzp8AK1gzotC/X9LsmKWQ/MoVeg5tjW3Iafs+1NkdThy9tu1emAPZFww8w= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:d580:abeb:bf6d:5726]) (user=glider job=sendgmr) by 2002:a05:6402:84a:b0:423:fe99:8c53 with SMTP id b10-20020a056402084a00b00423fe998c53mr25385277edz.195.1650991569448; Tue, 26 Apr 2022 09:46:09 -0700 (PDT) Date: Tue, 26 Apr 2022 18:43:11 +0200 In-Reply-To: <20220426164315.625149-1-glider@google.com> Message-Id: <20220426164315.625149-43-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 42/46] x86: kmsan: sync metadata pages on page fault 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-kernel@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 --- v2: -- addressed reports from kernel test robot Link: https://linux-review.googlesource.com/id/Ia5bd541e54f1ecc11b86666c3ec87c62ac0bdfb8 --- arch/x86/mm/fault.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index d0074c6ed31a3..f2250a32a10ca 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) +static void __arch_sync_kernel_mappings(unsigned long start, unsigned long end) { unsigned long addr; @@ -284,6 +284,27 @@ 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); +#ifdef CONFIG_KMSAN + /* + * 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 (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); + } +#endif +} + static bool low_pfn(unsigned long pfn) { return pfn < max_low_pfn; -- 2.36.0.rc2.479.g8af0fa9b8e-goog