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=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 1DBC0C433DF for ; Fri, 7 Aug 2020 06:24:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E03A622CAF for ; Fri, 7 Aug 2020 06:24:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596781496; bh=S2sPp8yJAEJgj7Ne6dgb7GSFRIi6Wr18HI7/MjMEu18=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=m2HJsDW6xBUyv6KgAqO3OdF/Tk1iq01bY5A0ARTMixx/K6eHQYvltBxnxDuzSY4Vu Gr5Pf4Wvf3XyZPKGfbZteOEF2g4/U2Qh8KW5QkIbGWu+4pNIC9p7xhuH2OFM8MZruj cwgeoLT5OF9Vm7r8ngjPhPqJ9kZnE7WaDFzBxzEw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726471AbgHGGY4 (ORCPT ); Fri, 7 Aug 2020 02:24:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:33716 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725379AbgHGGY4 (ORCPT ); Fri, 7 Aug 2020 02:24:56 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E9A7122CAE; Fri, 7 Aug 2020 06:24:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596781495; bh=S2sPp8yJAEJgj7Ne6dgb7GSFRIi6Wr18HI7/MjMEu18=; h=Date:From:To:Subject:In-Reply-To:From; b=XGTCHtjVyM7/RctviFooSY6RgFdv/IZC6f0iHj2rdY/Giu43E7ccrOonYOU8tjVqT he8JY8gvVp0t8xpfW6+/lGXmhaDSg9AJrOmVK5wWveouULmAdplKVzBdhNvIgcZWB2 EdyBYWCPVEHMWC4MPTc+NvvrfBdZJJ7hd1LJCz7Q= Date: Thu, 06 Aug 2020 23:24:54 -0700 From: Andrew Morton To: akpm@linux-foundation.org, andreyknvl@google.com, aryabinin@virtuozzo.com, dvyukov@google.com, glider@google.com, linux-mm@kvack.org, matthias.bgg@gmail.com, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, walter-zh.wu@mediatek.com Subject: [patch 135/163] lib/test_kasan.c: fix KASAN unit tests for tag-based KASAN Message-ID: <20200807062454.Z0mbAzTVt%akpm@linux-foundation.org> In-Reply-To: <20200806231643.a2711a608dd0f18bff2caf2b@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Walter Wu Subject: lib/test_kasan.c: fix KASAN unit tests for tag-based KASAN We use tag-based KASAN, then KASAN unit tests don't detect out-of-bounds memory access. They need to be fixed. With tag-based KASAN, the state of each 16 aligned bytes of memory is encoded in one shadow byte and the shadow value is tag of pointer, so we need to read next shadow byte, the shadow value is not equal to tag value of pointer, so that tag-based KASAN will detect out-of-bounds memory access. [walter-zh.wu@mediatek.com: use KASAN_SHADOW_SCALE_SIZE instead of 13] Link: http://lkml.kernel.org/r/20200708132524.11688-1-walter-zh.wu@mediatek.com Link: http://lkml.kernel.org/r/20200706115039.16750-1-walter-zh.wu@mediatek.com Signed-off-by: Walter Wu Suggested-by: Dmitry Vyukov Acked-by: Dmitry Vyukov Reviewed-by: Andrey Konovalov Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Matthias Brugger Signed-off-by: Andrew Morton --- lib/test_kasan.c | 49 +++++++++++++++++++++++++++++---------------- 1 file changed, 32 insertions(+), 17 deletions(-) --- a/lib/test_kasan.c~kasan-fix-kasan-unit-tests-for-tag-based-kasan +++ a/lib/test_kasan.c @@ -23,6 +23,10 @@ #include +#include "../mm/kasan/kasan.h" + +#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_SHADOW_SCALE_SIZE) + /* * We assign some test results to these globals to make sure the tests * are not eliminated as dead code. @@ -48,7 +52,8 @@ static noinline void __init kmalloc_oob_ return; } - ptr[size] = 'x'; + ptr[size + OOB_TAG_OFF] = 'x'; + kfree(ptr); } @@ -100,7 +105,8 @@ static noinline void __init kmalloc_page return; } - ptr[size] = 0; + ptr[size + OOB_TAG_OFF] = 0; + kfree(ptr); } @@ -170,7 +176,8 @@ static noinline void __init kmalloc_oob_ return; } - ptr2[size2] = 'x'; + ptr2[size2 + OOB_TAG_OFF] = 'x'; + kfree(ptr2); } @@ -188,7 +195,9 @@ static noinline void __init kmalloc_oob_ kfree(ptr1); return; } - ptr2[size2] = 'x'; + + ptr2[size2 + OOB_TAG_OFF] = 'x'; + kfree(ptr2); } @@ -224,7 +233,8 @@ static noinline void __init kmalloc_oob_ return; } - memset(ptr+7, 0, 2); + memset(ptr + 7 + OOB_TAG_OFF, 0, 2); + kfree(ptr); } @@ -240,7 +250,8 @@ static noinline void __init kmalloc_oob_ return; } - memset(ptr+5, 0, 4); + memset(ptr + 5 + OOB_TAG_OFF, 0, 4); + kfree(ptr); } @@ -257,7 +268,8 @@ static noinline void __init kmalloc_oob_ return; } - memset(ptr+1, 0, 8); + memset(ptr + 1 + OOB_TAG_OFF, 0, 8); + kfree(ptr); } @@ -273,7 +285,8 @@ static noinline void __init kmalloc_oob_ return; } - memset(ptr+1, 0, 16); + memset(ptr + 1 + OOB_TAG_OFF, 0, 16); + kfree(ptr); } @@ -289,7 +302,8 @@ static noinline void __init kmalloc_oob_ return; } - memset(ptr, 0, size+5); + memset(ptr, 0, size + 5 + OOB_TAG_OFF); + kfree(ptr); } @@ -423,7 +437,8 @@ static noinline void __init kmem_cache_o return; } - *p = p[size]; + *p = p[size + OOB_TAG_OFF]; + kmem_cache_free(cache, p); kmem_cache_destroy(cache); } @@ -520,25 +535,25 @@ static noinline void __init copy_user_te } pr_info("out-of-bounds in copy_from_user()\n"); - unused = copy_from_user(kmem, usermem, size + 1); + unused = copy_from_user(kmem, usermem, size + 1 + OOB_TAG_OFF); pr_info("out-of-bounds in copy_to_user()\n"); - unused = copy_to_user(usermem, kmem, size + 1); + unused = copy_to_user(usermem, kmem, size + 1 + OOB_TAG_OFF); pr_info("out-of-bounds in __copy_from_user()\n"); - unused = __copy_from_user(kmem, usermem, size + 1); + unused = __copy_from_user(kmem, usermem, size + 1 + OOB_TAG_OFF); pr_info("out-of-bounds in __copy_to_user()\n"); - unused = __copy_to_user(usermem, kmem, size + 1); + unused = __copy_to_user(usermem, kmem, size + 1 + OOB_TAG_OFF); pr_info("out-of-bounds in __copy_from_user_inatomic()\n"); - unused = __copy_from_user_inatomic(kmem, usermem, size + 1); + unused = __copy_from_user_inatomic(kmem, usermem, size + 1 + OOB_TAG_OFF); pr_info("out-of-bounds in __copy_to_user_inatomic()\n"); - unused = __copy_to_user_inatomic(usermem, kmem, size + 1); + unused = __copy_to_user_inatomic(usermem, kmem, size + 1 + OOB_TAG_OFF); pr_info("out-of-bounds in strncpy_from_user()\n"); - unused = strncpy_from_user(kmem, usermem, size + 1); + unused = strncpy_from_user(kmem, usermem, size + 1 + OOB_TAG_OFF); vm_munmap((unsigned long)usermem, PAGE_SIZE); kfree(kmem); _