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 X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5D32C433E0 for ; Mon, 1 Feb 2021 19:45:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A17F264EA8 for ; Mon, 1 Feb 2021 19:45:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230129AbhBATpZ (ORCPT ); Mon, 1 Feb 2021 14:45:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232446AbhBATob (ORCPT ); Mon, 1 Feb 2021 14:44:31 -0500 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 03121C0613ED for ; Mon, 1 Feb 2021 11:43:48 -0800 (PST) Received: by mail-qt1-x84a.google.com with SMTP id l15so11362476qtp.21 for ; Mon, 01 Feb 2021 11:43:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=5os4NdBbDONsbLVxABgdrPD9x64VnOptbOzgU3pEDKs=; b=icvI25ft44tZNJLareqZm2eV6LU3rjKFoSzXua9cf+7734+1fWcCmnYf7hEl5Qbz+D X1HGWJkAzxbfnIv7aZkYjPhjP0onDk8oLebvt5EFUyH9inK3uQ5w7A/juLiNsTrOpW6D 4QB/f/PJ605/JfJndxR6OL1twXraBxmad0by++3RFa1uvStOQIe+cLBvnXzyUaTfu+2v IDNsEAuTbXwUW2bZwOGOX6UO1kpsjI9ybzJEZjTQQpoYleLdUk5xqzFbAzvVhdKy/Qr8 WEoqEGKqEd0hnV7F9350O0q+eRFF2yKHGuEA4AGGamvMh48mEenN5FlPFbNm7at+3K3H B7wg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=5os4NdBbDONsbLVxABgdrPD9x64VnOptbOzgU3pEDKs=; b=DgtQahYbItWKyM8RollgtEQe3OfodN2mTW279RYEhPhkEG4K2TxPBrQcOXqqBMkssW LimM+qro8KYO6puvpuEgXvaU4V4b3oZO/7g8VgxIUxz9SZPuwv2TPNaFSiu+iDAftbrm 4K9aEwAt00hSKFyFSwM22YNz/45niRhfWp7RHiP7Y0rrFBB2KNtLixDFmElknT1R7BQh dBg0rS9DkenouQ8fs1Ngs0kXhIMzTdy4gBixRkCJ/6TVHik8zizUDQBUyimG0dWYkHCl AlMmCrGD4ylQUdlBc0rQ6EYg52ippLsP18Yrn/YggmYh5gpDM26DXiqyDMJ8nch/LZcj gwXQ== X-Gm-Message-State: AOAM531lylYIkNu0Qyu4YoN6uS9MwVL+Vuz8mkAMQ4DmzXMn0ZremoOk UKd1qzgvJcjHq8/DyfIFndohjjXDmtnx5ADR X-Google-Smtp-Source: ABdhPJzR+YEpFc2Ch11Rl6BTXMIoXfaJyZzPai737uCYCgWg2fJznC+a5+pVgD+X3paVHk7gPsjQcrXSotCeIBAj Sender: "andreyknvl via sendgmr" X-Received: from andreyknvl3.muc.corp.google.com ([2a00:79e0:15:13:7220:84ff:fe09:7e9d]) (user=andreyknvl job=sendgmr) by 2002:a0c:c488:: with SMTP id u8mr16899450qvi.9.1612208627196; Mon, 01 Feb 2021 11:43:47 -0800 (PST) Date: Mon, 1 Feb 2021 20:43:27 +0100 In-Reply-To: Message-Id: <8fdbf86842f4eaf2458ecd23d0844058dbc2c7a2.1612208222.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH 03/12] kasan: optimize large kmalloc poisoning From: Andrey Konovalov To: Catalin Marinas , Vincenzo Frascino , Dmitry Vyukov , Alexander Potapenko , Marco Elver Cc: Andrew Morton , Will Deacon , Andrey Ryabinin , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Similarly to kasan_kmalloc(), kasan_kmalloc_large() doesn't need to unpoison the object as it as already unpoisoned by alloc_pages() (or by ksize() for krealloc()). This patch changes kasan_kmalloc_large() to only poison the redzone. Signed-off-by: Andrey Konovalov --- mm/kasan/common.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 128cb330ca73..a7eb553c8e91 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -494,7 +494,6 @@ EXPORT_SYMBOL(__kasan_kmalloc); void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags) { - struct page *page; unsigned long redzone_start; unsigned long redzone_end; @@ -504,12 +503,23 @@ void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size, if (unlikely(ptr == NULL)) return NULL; - page = virt_to_page(ptr); + /* + * The object has already been unpoisoned by kasan_alloc_pages() for + * alloc_pages() or by ksize() for krealloc(). + */ + + /* + * The redzone has byte-level precision for the generic mode. + * Partially poison the last object granule to cover the unaligned + * part of the redzone. + */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + kasan_poison_last_granule(ptr, size); + + /* Poison the aligned part of the redzone. */ redzone_start = round_up((unsigned long)(ptr + size), KASAN_GRANULE_SIZE); - redzone_end = (unsigned long)ptr + page_size(page); - - kasan_unpoison(ptr, size); + redzone_end = (unsigned long)ptr + page_size(virt_to_page(ptr)); kasan_poison((void *)redzone_start, redzone_end - redzone_start, KASAN_PAGE_REDZONE); -- 2.30.0.365.g02bc693789-goog