From nobody Sun Oct 5 14:34:02 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 999DE80B for ; Fri, 1 Aug 2025 12:02:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754049762; cv=none; b=lUUPv3rw6iA6BQOaI47yZjiGPuRRZXIujPSVj9ZwuGkQfpGggiDudFI4OhmSeUD6R4j8kfFqxHHC/QyVWOsVXqNiecPPoPeJfGacewlFx6OJnv7KIHyBwu7syYzY3gk35WeXBCSMeLiD6HzPb8+OgDLRlFBqsW6w95uFMudspgc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754049762; c=relaxed/simple; bh=ZOH5WjKRJ5tUTyd3dy8PGVJZdah/OUl6IABtUIOhEO8=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=VNHWztx1+sW7H47fzF6265ARKsUGBVktrVs8BymwhvfHrE162ZMI8lJQcuIP576cS5zB26DKOGC5t4WtK+THCmHP3IKW/ZRknFn5vGKpL5Q04LQDjvPgDGX+Am98vbPNxCBYw0RA0S7tkxPqYnvEo/jHJQK9l/UFGTB0bVppueg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E5FAB1516; Fri, 1 Aug 2025 05:02:31 -0700 (PDT) Received: from e129823.cambridge.arm.com (e129823.arm.com [10.1.197.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4CEF43F673; Fri, 1 Aug 2025 05:02:38 -0700 (PDT) From: Yeoreum Yun To: thomas.weissschuh@linutronix.de, ryabinin.a.a@gmail.com, glider@google.com, andreyknvl@gmail.com, dvyukov@google.com, vincenzo.frascino@arm.com, akpm@linux-foundation.org Cc: kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yeoreum Yun Subject: [PATCH v3] kunit: kasan_test: disable fortify string checker on kasan_strings() test Date: Fri, 1 Aug 2025 13:02:36 +0100 Message-Id: <20250801120236.2962642-1-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Similar to commit 09c6304e38e4 ("kasan: test: fix compatibility with FORTIFY_SOURCE") the kernel is panicing in kasan_string(). This is due to the `src` and `ptr` not being hidden from the optimizer which would disable the runtime fortify string checker. Call trace: __fortify_panic+0x10/0x20 (P) kasan_strings+0x980/0x9b0 kunit_try_run_case+0x68/0x190 kunit_generic_run_threadfn_adapter+0x34/0x68 kthread+0x1c4/0x228 ret_from_fork+0x10/0x20 Code: d503233f a9bf7bfd 910003fd 9424b243 (d4210000) ---[ end trace 0000000000000000 ]--- note: kunit_try_catch[128] exited with irqs disabled note: kunit_try_catch[128] exited with preempt_count 1 # kasan_strings: try faulted: last ** replaying previous printk message ** # kasan_strings: try faulted: last line seen mm/kasan/kasan_test_c.c:1= 600 # kasan_strings: internal error occurred preventing test case from run= ning: -4 Signed-off-by: Yeoreum Yun --- Patch History =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D from v2 to v3: - rewrite commit message. - Using OPTIMIZER_HIDE_VAR() instead of __NO_FORTIFY - https://lore.kernel.org/all/20250801092805.2602490-1-yeoreum.yun@arm.co= m/ from v1 to v2: - Using __NO_FORTIFY instead of skipping kasan_strings() when CONFIG_FORTIFY_SOURCE is enabled. - https://lore.kernel.org/all/aIs4rwZ1o53iTuP%2F@e129823.arm.com/ --- mm/kasan/kasan_test_c.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/kasan/kasan_test_c.c b/mm/kasan/kasan_test_c.c index 5f922dd38ffa..a1a0e60645da 100644 --- a/mm/kasan/kasan_test_c.c +++ b/mm/kasan/kasan_test_c.c @@ -1578,9 +1578,11 @@ static void kasan_strings(struct kunit *test) ptr =3D kmalloc(size, GFP_KERNEL | __GFP_ZERO); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + OPTIMIZER_HIDE_VAR(ptr); src =3D kmalloc(KASAN_GRANULE_SIZE, GFP_KERNEL | __GFP_ZERO); strscpy(src, "f0cacc1a0000000", KASAN_GRANULE_SIZE); + OPTIMIZER_HIDE_VAR(src); /* * Make sure that strscpy() does not trigger KASAN if it overreads into -- LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}