From patchwork Thu Aug 8 08:15:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13757103 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 81C59188CA4; Thu, 8 Aug 2024 08:17:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723105064; cv=none; b=Nyr0Eu8Ivbg4F0w+lnZhi2rfyEv0GW8HpMkJKydaTY5PpJEUkdOUIfJJ1/8qY8rHy1ioGLlUKMC/kK7kFnRk8yuuz8mflbD5ZJZyut8vQhnGmyOn0g2V3KP7DkyC+7cxgkBj5WsXVma94EHfRkAshvMRcPrxBFmZmg0BoHYsUbk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723105064; c=relaxed/simple; bh=OrLlJZLIdpu8469ekNLVgxT7+eFxGI9yqTN5LZeTdZg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ah1F+O+HjTCPWecTQlwdm+7frdJDgYdi2yMLnQiEHljXM+shDfiT6UTzXEOqeMjnkgUIKjgJjBJpc+1v1jjlIlma0bemVX4rSa54UYCvOkuUQZ4P5pEmsyyU1VLSiMVOuXec0rJZkFFkEXwIVlBHGxp2EeQbNIkPaTym18dD2rY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ioxw37Oi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ioxw37Oi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 82CCCC4AF16; Thu, 8 Aug 2024 08:17:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723105064; bh=OrLlJZLIdpu8469ekNLVgxT7+eFxGI9yqTN5LZeTdZg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=Ioxw37Oima6PVBah/shmp5Ter51Q/TISbJaYTLYUASaTIgzJBlo7dhI/v6psdMgSI MyqkYhE5WLwbj1iOUxpWxDrDD1OBiR6QvzdoJRgZQB7UND7omn0dfxEJcU+PYrYtjt V73qb2Z4dGXvtvO/rk/l6bklY+qkWSiRLbAe41EVnMj/kOjyBBr0Thq5de+OCys3d7 NcvZ4QciF/viz2orK3T+0lvdS9FQ8ixl6cy7xLta+Hg29+GXTtktnlr9lflDJ3SJiH N560rbGY7rKu2amZQUwXQhvOeSDuPigVzhumlCHLYg9gvzkEGEBpWbVVaw8pQuBoO9 iHsLISpy+eiDQ== From: Mark Brown Date: Thu, 08 Aug 2024 09:15:29 +0100 Subject: [PATCH RFT v8 8/9] selftests/clone3: Allow tests to flag if -E2BIG is a valid error code Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240808-clone3-shadow-stack-v8-8-0acf37caf14c@kernel.org> References: <20240808-clone3-shadow-stack-v8-0-0acf37caf14c@kernel.org> In-Reply-To: <20240808-clone3-shadow-stack-v8-0-0acf37caf14c@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , jannh@google.com, bsegall@google.com, linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown , Kees Cook X-Mailer: b4 0.15-dev-37811 X-Developer-Signature: v=1; a=openpgp-sha256; l=1887; i=broonie@kernel.org; h=from:subject:message-id; bh=OrLlJZLIdpu8469ekNLVgxT7+eFxGI9yqTN5LZeTdZg=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBmtH7PF8qRF2BJmh32y0RmrHBzpwv8UR9FcqUq4 jSMVpDSLRWJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZrR+zwAKCRAk1otyXVSH 0C5XB/0cRSLnJkkl/RUdqEyjK4e+rrlHnGZ3l1sf7QgUfhJAfjRIjUcNwvf0eV0+QBsa+kIIglQ 348zMED92ZaZ+qQbrlbDtdl7vKd+B5QYU2u4RR1pHr2yc7ZJ1vB5Ts0WSnw/OkRyuH73CuNZ6X7 lDjHb0h21KhsspDThWrU2dWOpKHCceJWkYmY+A+wBuL1H2O2WZ2bxg9h49ia1ukFE2U0izn8Qf9 yn/a5tA2PXWGGNYwrm/CtB9l/ATWbWy9c1UGF2qL5SS6k3qXHaNNcM2OErisBRJvQMhqgJMp/d/ MfgG8xekX8ppkSlVEad5S4Y3rRg+FKbmbZYNreOrrsYt+LYq X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB The clone_args structure is extensible, with the syscall passing in the length of the structure. Inside the kernel we use copy_struct_from_user() to read the struct but this has the unfortunate side effect of silently accepting some overrun in the structure size providing the extra data is all zeros. This means that we can't discover the clone3() features that the running kernel supports by simply probing with various struct sizes. We need to check this for the benefit of test systems which run newer kselftests on old kernels. Add a flag which can be set on a test to indicate that clone3() may return -E2BIG due to the use of newer struct versions. Currently no tests need this but it will become an issue for testing clone3() support for shadow stacks, the support for shadow stacks is already present on x86. Signed-off-by: Mark Brown --- tools/testing/selftests/clone3/clone3.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/testing/selftests/clone3/clone3.c b/tools/testing/selftests/clone3/clone3.c index 3b3a08e6a34d..26221661e9ae 100644 --- a/tools/testing/selftests/clone3/clone3.c +++ b/tools/testing/selftests/clone3/clone3.c @@ -39,6 +39,7 @@ struct test { size_t size; size_function size_function; int expected; + bool e2big_valid; enum test_mode test_mode; filter_function filter; }; @@ -153,6 +154,11 @@ static void test_clone3(const struct test *test) ksft_print_msg("[%d] clone3() with flags says: %d expected %d\n", getpid(), ret, test->expected); if (ret != test->expected) { + if (test->e2big_valid && ret == -E2BIG) { + ksft_print_msg("Test reported -E2BIG\n"); + ksft_test_result_skip("%s\n", test->name); + return; + } ksft_print_msg( "[%d] Result (%d) is different than expected (%d)\n", getpid(), ret, test->expected);