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 71854C433DB for ; Mon, 1 Feb 2021 19:46:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E0C564EA9 for ; Mon, 1 Feb 2021 19:46:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231426AbhBATpw (ORCPT ); Mon, 1 Feb 2021 14:45:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231326AbhBATox (ORCPT ); Mon, 1 Feb 2021 14:44:53 -0500 Received: from mail-wr1-x44a.google.com (mail-wr1-x44a.google.com [IPv6:2a00:1450:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 48A17C061786 for ; Mon, 1 Feb 2021 11:43:53 -0800 (PST) Received: by mail-wr1-x44a.google.com with SMTP id d7so11038418wri.23 for ; Mon, 01 Feb 2021 11:43:53 -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=BaU4zsBnF6d3TSTU+6bwjMLYV3de6hEhX75uuk8b+O4=; b=nJiXwOEo+jDWjutl3bPtMddLIEbYjySSqFB9nsRMPC/OyMH1cWW9MJCeCANQqWCKmB 4mwP+1VFCx3hJfom58GEOvLp6QCaI9DthbxNDJt5E19vA2IenGYT//kFZ3tt5SKMwPII JUvkgGhGqUDAruV7bZhAZMJVREM4TVtH2aoavGSYKjlNdtFGTAYff54a63RosxywMuHm 1rEjzRp24e2Mh+Qobh7XPtIFaq29nychvE8goMeWtgJmRCYM9XxEicpGU9vrO7yzeJf3 0BwkX+2NT+5+L7FlbRszkE0nJeL7H4X8e4lzext+ZMwX8Dzov8Ow4AQrlTK8RDIsbmNp XaFw== 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=BaU4zsBnF6d3TSTU+6bwjMLYV3de6hEhX75uuk8b+O4=; b=NB2QM9kxypoRz3mM3Bgh4nS0d1R3dB2ReP6OieojM1OqbutZJXxObUm46iwdIFGrF8 5YKc/AwJf2QZ15vCkSEbaRLb98sKseuWNgmjhDwvtQ947A1VUPfXYT5Nmh3+FVYr5nlr q/Znw39/c3MrxMevdH0GwFWs7d9gNi2ZRIslPv7p5ayVgQto4gJLnLPBlEdWCSpmLLRd 3Rj/m1ToaUjtWS/U3h/q0AattRxXC2pjzo+/q4a/3ag97tNJtK+YJW+kDVDrwBBfkpBt SVOLfqaxEK6tf4DbA2EwKxyFeqUPtpeWZwY5hKzgvRUvqF7TXV3FblyznWcpGuuiCF9c D7Pw== X-Gm-Message-State: AOAM5325IRcbhBw7dU5VJTJ+KYLMa09l06UQdk4MJC9hF4uTUYcNQJgQ t0XvD782NSw7pTFRLot685PgKAaL4PESDgLh X-Google-Smtp-Source: ABdhPJw57hRKvoeOE3jkg8dsfKFGhvdZTC70UClQcRWBXmSodKiJDsoN3TWrUtEegspLXmVAevtVI9fb+W66gF3H 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:a1c:6a02:: with SMTP id f2mr447589wmc.36.1612208631997; Mon, 01 Feb 2021 11:43:51 -0800 (PST) Date: Mon, 1 Feb 2021 20:43:29 +0100 In-Reply-To: Message-Id: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH 05/12] kasan: unify large kfree checks 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 Unify checks in kasan_kfree_large() and in kasan_slab_free_mempool() for large allocations as it's done for small kfree() allocations. With this change, kasan_slab_free_mempool() starts checking that the first byte of the memory that's being freed is accessible. Signed-off-by: Andrey Konovalov --- include/linux/kasan.h | 16 ++++++++-------- mm/kasan/common.c | 36 ++++++++++++++++++++++++++---------- 2 files changed, 34 insertions(+), 18 deletions(-) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 2d5de4092185..d53ea3c047bc 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -200,6 +200,13 @@ static __always_inline bool kasan_slab_free(struct kmem_cache *s, void *object) return false; } +void __kasan_kfree_large(void *ptr, unsigned long ip); +static __always_inline void kasan_kfree_large(void *ptr) +{ + if (kasan_enabled()) + __kasan_kfree_large(ptr, _RET_IP_); +} + void __kasan_slab_free_mempool(void *ptr, unsigned long ip); static __always_inline void kasan_slab_free_mempool(void *ptr) { @@ -247,13 +254,6 @@ static __always_inline void * __must_check kasan_krealloc(const void *object, return (void *)object; } -void __kasan_kfree_large(void *ptr, unsigned long ip); -static __always_inline void kasan_kfree_large(void *ptr) -{ - if (kasan_enabled()) - __kasan_kfree_large(ptr, _RET_IP_); -} - /* * Unlike kasan_check_read/write(), kasan_check_byte() is performed even for * the hardware tag-based mode that doesn't rely on compiler instrumentation. @@ -302,6 +302,7 @@ static inline bool kasan_slab_free(struct kmem_cache *s, void *object) { return false; } +static inline void kasan_kfree_large(void *ptr) {} static inline void kasan_slab_free_mempool(void *ptr) {} static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags) @@ -322,7 +323,6 @@ static inline void *kasan_krealloc(const void *object, size_t new_size, { return (void *)object; } -static inline void kasan_kfree_large(void *ptr) {} static inline bool kasan_check_byte(const void *address) { return true; diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 086bb77292b6..9c64a00bbf9c 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -364,6 +364,31 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip) return ____kasan_slab_free(cache, object, ip, true); } +static bool ____kasan_kfree_large(void *ptr, unsigned long ip) +{ + if (ptr != page_address(virt_to_head_page(ptr))) { + kasan_report_invalid_free(ptr, ip); + return true; + } + + if (!kasan_byte_accessible(ptr)) { + kasan_report_invalid_free(ptr, ip); + return true; + } + + /* + * The object will be poisoned by kasan_free_pages() or + * kasan_slab_free_mempool(). + */ + + return false; +} + +void __kasan_kfree_large(void *ptr, unsigned long ip) +{ + ____kasan_kfree_large(ptr, ip); +} + void __kasan_slab_free_mempool(void *ptr, unsigned long ip) { struct page *page; @@ -377,10 +402,8 @@ void __kasan_slab_free_mempool(void *ptr, unsigned long ip) * KMALLOC_MAX_SIZE, and kmalloc falls back onto page_alloc. */ if (unlikely(!PageSlab(page))) { - if (ptr != page_address(page)) { - kasan_report_invalid_free(ptr, ip); + if (____kasan_kfree_large(ptr, ip)) return; - } kasan_poison(ptr, page_size(page), KASAN_FREE_PAGE); } else { ____kasan_slab_free(page->slab_cache, ptr, ip, false); @@ -539,13 +562,6 @@ void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flag return ____kasan_kmalloc(page->slab_cache, object, size, flags); } -void __kasan_kfree_large(void *ptr, unsigned long ip) -{ - if (ptr != page_address(virt_to_head_page(ptr))) - kasan_report_invalid_free(ptr, ip); - /* The object will be poisoned by kasan_free_pages(). */ -} - bool __kasan_check_byte(const void *address, unsigned long ip) { if (!kasan_byte_accessible(address)) { -- 2.30.0.365.g02bc693789-goog