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 96C14C433DB for ; Fri, 5 Feb 2021 23:47:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5715C64FA7 for ; Fri, 5 Feb 2021 23:47:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231393AbhBEXqV (ORCPT ); Fri, 5 Feb 2021 18:46:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231793AbhBEORW (ORCPT ); Fri, 5 Feb 2021 09:17:22 -0500 Received: from mail-pj1-x1049.google.com (mail-pj1-x1049.google.com [IPv6:2607:f8b0:4864:20::1049]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6598FC061224 for ; Fri, 5 Feb 2021 07:47:24 -0800 (PST) Received: by mail-pj1-x1049.google.com with SMTP id b4so4505708pji.4 for ; Fri, 05 Feb 2021 07:47:24 -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=tljlSxhBzcxqidAVSdVdhM6oUJ+nJ3d1xitEmX2Ppf0=; b=syVSGwpY7OBUajXhF+JU66oy4DayPtyhrZEKrCctZ7ZSEwdKPb5Fvf+ONRWcDtxp0K l36gKS8Yr71bsitJfXedVqVkHwOpQH2t/7/hBm4ZmVz/jpErYZ6yrtAzAzFjr4bLp1mg ZNGlS6epLYCc6jCq4C1m6SSWpMXkg7iVv0VbgQuORm2mYYrrw/8PmMphfXzVC3yZ6Lv6 f992UftKMf+GCjLbYmegMakIMsmuEpSMOCwEwtz+LdHiElyCXXWkfY9EjfKHBoHqkLxc tuCvq3A1ZCy11mG8Rs7N3bouZpjWecOu83K6/n5Uzv6c/sKJo2krn++2hCMlongp3G5K c3Zg== 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=tljlSxhBzcxqidAVSdVdhM6oUJ+nJ3d1xitEmX2Ppf0=; b=j2OjBsjkzN7LEseBhmIGAb3f3Lg2wf7ADwyGdVNFTy51pnSTxNHglvpKSmnKU+ghrs vM0IZz6BR0mHU2bUtIr44byKFqeJvAJeywBap8rDNaz/ir3u9Rtc2ilPzkbNs7Uxa2Cx D4bWoZA3Y7xczK6oSFDhshcEDWxEwpGXUnSgjrFQMZ1+dxFcWWkCkYLQ3sCnCmTJus/A TLNMRQkz8RBuxIcFp5x1eHNhNxREA7AcDnOZaKQKPW48Zmvn8esQmpeYbt4hDzEBUYtr kmGFR0yDAJYvMxlDIVBEiIF2F2ovAufK5lKWmf8f54yxI4MT1t5DHxQQPhCIntNBcwdy IHmg== X-Gm-Message-State: AOAM530AQVUVmdegMuP1rs3h4GJOQW7dEDvTzM7em1X18VKRNma8+Ms+ M3Kk3PaitsWMtZYVXfUblpZUZCnpGNkKUpN5 X-Google-Smtp-Source: ABdhPJyO1MocpYFwZ1RXJ8jVPh8e1tllN7Hw4na0XycrZ5x/iFUpbgSITGryg5kyrNeA7pCK+1dElwIgxYqVy2a5 Sender: "andreyknvl via sendgmr" X-Received: from andreyknvl3.muc.corp.google.com ([2a00:79e0:15:13:edb8:b79c:2e20:e531]) (user=andreyknvl job=sendgmr) by 2002:a0c:f94a:: with SMTP id i10mr4890478qvo.22.1612539565151; Fri, 05 Feb 2021 07:39:25 -0800 (PST) Date: Fri, 5 Feb 2021 16:39:04 +0100 In-Reply-To: Message-Id: <97581e50e594596e0bf8dd5bb3598d5e13013f18.1612538932.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH v2 03/12] kasan: optimize large kmalloc poisoning From: Andrey Konovalov To: Andrew Morton , Catalin Marinas , Vincenzo Frascino , Dmitry Vyukov , Alexander Potapenko , Marco Elver Cc: 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. Reviewed-by: Marco Elver 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 00edbc3eb32e..f2a6bae13053 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