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 64F5CC433EF for ; Fri, 1 Jul 2022 14:29:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230414AbiGAO3s (ORCPT ); Fri, 1 Jul 2022 10:29:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48232 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232544AbiGAO2s (ORCPT ); Fri, 1 Jul 2022 10:28:48 -0400 Received: from mail-ed1-x549.google.com (mail-ed1-x549.google.com [IPv6:2a00:1450:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C34D677D1 for ; Fri, 1 Jul 2022 07:25:10 -0700 (PDT) Received: by mail-ed1-x549.google.com with SMTP id g7-20020a056402424700b00435ac9c7a8bso1878598edb.14 for ; Fri, 01 Jul 2022 07:25:10 -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=Hs1LG4gEZrL61QQbW1yHjuo38dVFxHr6aTHqGRd2nIU=; b=R1eUqKBbN6WzWIjXxRI2PDbx29b9tpJSiig3/YaznmdOIZ/neK78PvIj5Cl/JjgB/w 9SfdvW2BtOiP89nS8ThzmS35SU1A6VUk9hiJALgX6yvIEpuomqcW5bDLzgsEQ013f6rk rFf3VUovNXoIf4KVP4MMfWUh7tsgq1WO5Pa9II9uYW0yZdgX2/mSo5GXmSL2H/ZwJwsd uxM4RIZS+4NPzi2RYwgUcpKcS16h49QlGgoZ05LwFfkprgCDz5UPO4MlYHJZ5DPrqB+x 6AHtkpJzEpLuNlHTmvU9jllU2HKPHg+40cmHHxveZn6WEswHaMpjdduncEJv7l8ri3sA Qcyg== 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=Hs1LG4gEZrL61QQbW1yHjuo38dVFxHr6aTHqGRd2nIU=; b=oUHTiMffRBKuuusPBO5Sa7v7Hq4etHBVRoDjevB13CggiAu0dcRgBQibW0hGKKpK0S OJB6Uw7ZGrS3IQPfnWEM/VcvrxOlq1Cc5F6kMC5wrqzgIULGfAeUdPY6gzFrqHQpfBAj /QtHkCD9SVhhD8PGyL8JqyOLF4gn7Ygus1MjpNjSF+iLLc9O/yhOvIzm6G4pd2i2Kl1s AjgrmX8do/QWojyo7WhFM8NFHJyFZX2oNHhvrqlKrWOVm3sjZY8/HMjlG6Ydjpf3Z5EY wxRWSZIu6EHymdc3fYG9QNEQA9dNKPpG4qg1T1IkZcMJE5Rz5ZgGmXGxSAruMvyzY1Eg UdYA== X-Gm-Message-State: AJIora/EjCmxjv9Ha6R9ufLmw62ArqVM8dyXocg2FLrqKlYtRUWdYmMX WRW+iD5sWb49SeOGBwomr9KTtUX/WL4= X-Google-Smtp-Source: AGRyM1sHhTsQ0hcpXEAMUmnlfkHECIs68+d9wOkDzkI+VoyBaJw2lW70YlMf+nBUJARdbRgd+2PdvDTFpog= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:a6f5:f713:759c:abb6]) (user=glider job=sendgmr) by 2002:a17:906:846c:b0:72a:4b4f:b1b1 with SMTP id hx12-20020a170906846c00b0072a4b4fb1b1mr11506007ejc.255.1656685499239; Fri, 01 Jul 2022 07:24:59 -0700 (PDT) Date: Fri, 1 Jul 2022 16:23:02 +0200 In-Reply-To: <20220701142310.2188015-1-glider@google.com> Message-Id: <20220701142310.2188015-38-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 37/45] x86: kmsan: sync metadata pages on page fault 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 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 fad8faa29d042..d07fe0801f203 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; -- 2.37.0.rc0.161.g10f37bed90-goog