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 783D5C433FE for ; Tue, 29 Mar 2022 12:54:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236841AbiC2M4e (ORCPT ); Tue, 29 Mar 2022 08:56:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236849AbiC2M4V (ORCPT ); Tue, 29 Mar 2022 08:56:21 -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 19BA725B93E for ; Tue, 29 Mar 2022 05:42:27 -0700 (PDT) Received: by mail-ej1-x64a.google.com with SMTP id zd21-20020a17090698d500b006df778721f7so8058430ejb.3 for ; Tue, 29 Mar 2022 05:42:27 -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=GRTJFN5fI/eCQ6Ah2RQjb7/dqw7JAuAGzue9isPThnU=; b=V2A969r8azagnZbvbCjDak0q6MRkqtC8n5tFydFSoeWA+AZwbef6NPKlrrU+H+BRBM P6taNp8QY9FavRqmNYSwqrdYGQ97zsjJxhBcCNj+utxQuJ9nOPiopPtbBqzQ8gBr6Qzm 7SYENQDGsHWHESxdBNNfqefvYaEkKbqQ7Uw9rn3v77vq15hOdIJrJeEt188vunugqZcn Y6At8xC/ehmqb5IdQtbwYrfxqEDNNN28/KTOPS67Mp49F5QHDODlthVjEKpkMZlKaPm0 nF0jHasnFvBSUC3gLePFYURhT77L4PhtEKIV+vHO9KG0REyFSTNFBTme4w/CaQQAv4EV cm0Q== 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=GRTJFN5fI/eCQ6Ah2RQjb7/dqw7JAuAGzue9isPThnU=; b=TL8rh0nsyfGouOR/UymreTTMNokIsirBnjWPSeNOzTZQ0Ezyubqrcvgl545pasaIKP l8hRbw/77szEdwbTFwPYQ0Pe/shnOxUMd/rySvQOvHe3fLQS7JcdkpNK5xX832gmq8rV w3/gfkBByZkoBa4awAMOxiHuN2Ws5gQDvCEEdWYDqjnYqUkGAOML2tVmpjMn//+uE3RJ 1lz86+D/j+NpiR5hsv4R83jaK15P4uA5rfDCunhoBDpt7vHLoaELFR2xT4lQ6PomIwse wb08IiLHwTw1m+AuOQBundX3zdFM+tIQTeiKDSXuq1AbYzwyKWlj95MaG+/WgazMMY3N UYKw== X-Gm-Message-State: AOAM531RQmFLn1bXFVt4YnzUnkuzQOKrf7aePzeJZiJ5ifnOsrFnGxyu VuH9JW/ZAWMlHqGNFNH57oBjfbtVks4= X-Google-Smtp-Source: ABdhPJzeBfVX40XVB+0DxQzCOfCbyY7YIWfJ+7MS3btbGbfEX8I9gsHnpMWWbEmqsPh4mt6QWJwzC2vkQok= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:36eb:759:798f:98c3]) (user=glider job=sendgmr) by 2002:a17:907:c02:b0:6df:fb64:2770 with SMTP id ga2-20020a1709070c0200b006dffb642770mr34762165ejc.221.1648557746364; Tue, 29 Mar 2022 05:42:26 -0700 (PDT) Date: Tue, 29 Mar 2022 14:40:13 +0200 In-Reply-To: <20220329124017.737571-1-glider@google.com> Message-Id: <20220329124017.737571-45-glider@google.com> Mime-Version: 1.0 References: <20220329124017.737571-1-glider@google.com> X-Mailer: git-send-email 2.35.1.1021.g381101b075-goog Subject: [PATCH v2 44/48] 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 , 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 --- 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; -- 2.35.1.1021.g381101b075-goog