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=-16.6 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 7C107C433E0 for ; Thu, 14 Jan 2021 19:37:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 191BC2399C for ; Thu, 14 Jan 2021 19:37:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 191BC2399C Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A267D8D0128; Thu, 14 Jan 2021 14:36:57 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9AF558D0129; Thu, 14 Jan 2021 14:36:57 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 73C0D8D0128; Thu, 14 Jan 2021 14:36:57 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0152.hostedemail.com [216.40.44.152]) by kanga.kvack.org (Postfix) with ESMTP id 5A1AD8D0127 for ; Thu, 14 Jan 2021 14:36:57 -0500 (EST) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 290BE180AD815 for ; Thu, 14 Jan 2021 19:36:57 +0000 (UTC) X-FDA: 77705388474.01.snail05_07163fa27529 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin01.hostedemail.com (Postfix) with ESMTP id 04FE710053C1C for ; Thu, 14 Jan 2021 19:36:56 +0000 (UTC) X-HE-Tag: snail05_07163fa27529 X-Filterd-Recvd-Size: 5045 Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) by imf13.hostedemail.com (Postfix) with ESMTP for ; Thu, 14 Jan 2021 19:36:56 +0000 (UTC) Received: by mail-wr1-f73.google.com with SMTP id u29so3063093wru.6 for ; Thu, 14 Jan 2021 11:36:56 -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=BYOOBCCudRU7Lchp5NpxZrw19s2hqbj4Q5eYKa3nns4=; b=rTUv5m0zNhD34FCcwlpq09FOQVY979bNJORsUf6OmzgaoTAOFMWsj6uKVvVPryAncc Y6OhafJM04uWVc9pjJQKH5NCt3DkQiMm85OpEihWPA8JcD25gC3aeR9kvA9Y7WWCW9ie EmLUYPTYMJpoVS5omyVpvjA8KTO6StvqomYrsX+za0mQvc8oQwUxEjeGb11XkDrHA5Ee Szowzviwu7DMZ/YWR074GrBN8wKOLaOqezsuVaixBa1pbB8unyc+XyrVbX7S7Hr4U0Jt MYp20quJAyjR5U7eAr6/jrLyH1zjC5WXJT5NxhYC5GL61NwjGH+LqPS61lk6rSQ+HQeG bkqA== 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=BYOOBCCudRU7Lchp5NpxZrw19s2hqbj4Q5eYKa3nns4=; b=QzcnZkCsnENHfXMdJiaH9aQGWuFLosuuYdXoy3EAWfPMMUcNmjw1qQeTj93kPTJwqt NGggM5I81o1x452ZOboUQhYaj2zQMcX9GU5BbrRN6zr0Hs4jnqigrtIefCjhBf/8TF6V fPTurMPy3pIkOep6T6Q5o6gl4dTAPmH1DBxOtSyAmNZvuNgpneIvuPaSHK/FraqGyYw9 vj6uPWy1DIyDRyMgoS225gCLTtX1ssZ+F/UfmWntgWIch9faBY25eID2XuYd+xtxopEl 81AFxRVthVqAZq39rW5f6wNyHfktggq0rePabIkb5t+RjRjbixkm+vMRwNyEgEyZVjdn kvZQ== X-Gm-Message-State: AOAM533KloUmqvF3U4dkntVcKdEzI0x/Fg3WrnX7mIGvklxrJ5K62VKL C6CPuyhf9HSrFt4dBUbnceCv201B/4+UoDtf X-Google-Smtp-Source: ABdhPJyYO2MlxfR/Y4/edLSR5eTxNluzpB8ZY4biV8IiJKVDxm5JrKLOUsXrzNZQUnUIvM0PtVPM014fSmcVbUqw X-Received: from andreyknvl3.muc.corp.google.com ([2a00:79e0:15:13:7220:84ff:fe09:7e9d]) (user=andreyknvl job=sendgmr) by 2002:a05:600c:2905:: with SMTP id i5mr5291713wmd.28.1610653015397; Thu, 14 Jan 2021 11:36:55 -0800 (PST) Date: Thu, 14 Jan 2021 20:36:25 +0100 In-Reply-To: Message-Id: <62a4d6dba701ad4747d836fb08c20fdfffc701f8.1610652890.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.30.0.284.gd98b1dd5eaa7-goog Subject: [PATCH v3 09/15] kasan: adapt kmalloc_uaf2 test to HW_TAGS mode 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" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: In the kmalloc_uaf2() test, the pointers to the two allocated memory blocks might happen to be the same, and the test will fail. With the software tag-based mode, the probability of the that is 1/254, so it's hard to observe the failure. For the hardware tag-based mode though, the probablity is 1/14, which is quite noticable. Allow up to 16 attempts at generating different tags for the tag-based modes. Link: https://linux-review.googlesource.com/id/Ibfa458ef2804ff465d8eb07434a300bf36388d55 Reviewed-by: Marco Elver Reviewed-by: Alexander Potapenko Signed-off-by: Andrey Konovalov --- lib/test_kasan.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/lib/test_kasan.c b/lib/test_kasan.c index 2419e36e117b..0cda4a1ff394 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -382,7 +382,9 @@ static void kmalloc_uaf2(struct kunit *test) { char *ptr1, *ptr2; size_t size = 43; + int counter = 0; +again: ptr1 = kmalloc(size, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); @@ -391,6 +393,15 @@ static void kmalloc_uaf2(struct kunit *test) ptr2 = kmalloc(size, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + /* + * For tag-based KASAN ptr1 and ptr2 tags might happen to be the same. + * Allow up to 16 attempts at generating different tags. + */ + if (!IS_ENABLED(CONFIG_KASAN_GENERIC) && ptr1 == ptr2 && counter++ < 16) { + kfree(ptr2); + goto again; + } + KUNIT_EXPECT_KASAN_FAIL(test, ptr1[40] = 'x'); KUNIT_EXPECT_PTR_NE(test, ptr1, ptr2); -- 2.30.0.284.gd98b1dd5eaa7-goog