From patchwork Thu Apr 22 04:48:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Chang S. Bae" X-Patchwork-Id: 12217631 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 3C7EEC43460 for ; Thu, 22 Apr 2021 04:54:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 236C261460 for ; Thu, 22 Apr 2021 04:54:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229569AbhDVEyz (ORCPT ); Thu, 22 Apr 2021 00:54:55 -0400 Received: from mga18.intel.com ([134.134.136.126]:45527 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231835AbhDVEyy (ORCPT ); Thu, 22 Apr 2021 00:54:54 -0400 IronPort-SDR: nv1p1lStpkrVp04FxXwjIwbWySWCUvHlvRiX5SuA8BuU1Pn414tMWkPeT/RC6YbKwRKG4BuZPi dXa17VLBYdjA== X-IronPort-AV: E=McAfee;i="6200,9189,9961"; a="183311517" X-IronPort-AV: E=Sophos;i="5.82,241,1613462400"; d="scan'208";a="183311517" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Apr 2021 21:54:16 -0700 IronPort-SDR: CES5bOafo6TZK1iWvIl+/rBYuqCI+s3PUh5DebUf9kiD3TId0wolu/cbZ6PpPaCdiEBVz5n/6n 2wMN+XkUhHxg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,241,1613462400"; d="scan'208";a="524515414" Received: from chang-linux-3.sc.intel.com ([172.25.66.175]) by fmsmga001.fm.intel.com with ESMTP; 21 Apr 2021 21:54:16 -0700 From: "Chang S. Bae" To: bp@suse.de, tglx@linutronix.de, mingo@kernel.org, luto@kernel.org, x86@kernel.org Cc: len.brown@intel.com, dave.hansen@intel.com, hjl.tools@gmail.com, Dave.Martin@arm.com, jannh@google.com, mpe@ellerman.id.au, carlos@redhat.com, tony.luck@intel.com, ravi.v.shankar@intel.com, libc-alpha@sourceware.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, chang.seok.bae@intel.com, linux-kselftest@vger.kernel.org Subject: [PATCH v8 4/6] selftest/sigaltstack: Use the AT_MINSIGSTKSZ aux vector if available Date: Wed, 21 Apr 2021 21:48:54 -0700 Message-Id: <20210422044856.27250-5-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210422044856.27250-1-chang.seok.bae@intel.com> References: <20210422044856.27250-1-chang.seok.bae@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org The SIGSTKSZ constant may not represent enough stack size in some architectures as the hardware state size grows. Use getauxval(AT_MINSIGSTKSZ) to increase the stack size. Signed-off-by: Chang S. Bae Reviewed-by: Len Brown Cc: linux-kselftest@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- Changes from v5: * Added as a new patch. --- tools/testing/selftests/sigaltstack/sas.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/sigaltstack/sas.c b/tools/testing/selftests/sigaltstack/sas.c index 8934a3766d20..c53b070755b6 100644 --- a/tools/testing/selftests/sigaltstack/sas.c +++ b/tools/testing/selftests/sigaltstack/sas.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "../kselftest.h" @@ -24,6 +25,11 @@ #define SS_AUTODISARM (1U << 31) #endif +#ifndef AT_MINSIGSTKSZ +#define AT_MINSIGSTKSZ 51 +#endif + +static unsigned int stack_size; static void *sstack, *ustack; static ucontext_t uc, sc; static const char *msg = "[OK]\tStack preserved"; @@ -47,7 +53,7 @@ void my_usr1(int sig, siginfo_t *si, void *u) #endif if (sp < (unsigned long)sstack || - sp >= (unsigned long)sstack + SIGSTKSZ) { + sp >= (unsigned long)sstack + stack_size) { ksft_exit_fail_msg("SP is not on sigaltstack\n"); } /* put some data on stack. other sighandler will try to overwrite it */ @@ -108,6 +114,10 @@ int main(void) stack_t stk; int err; + /* Make sure more than the required minimum. */ + stack_size = getauxval(AT_MINSIGSTKSZ) + SIGSTKSZ; + ksft_print_msg("[NOTE]\tthe stack size is %lu\n", stack_size); + ksft_print_header(); ksft_set_plan(3); @@ -117,7 +127,7 @@ int main(void) sigaction(SIGUSR1, &act, NULL); act.sa_sigaction = my_usr2; sigaction(SIGUSR2, &act, NULL); - sstack = mmap(NULL, SIGSTKSZ, PROT_READ | PROT_WRITE, + sstack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0); if (sstack == MAP_FAILED) { ksft_exit_fail_msg("mmap() - %s\n", strerror(errno)); @@ -139,7 +149,7 @@ int main(void) } stk.ss_sp = sstack; - stk.ss_size = SIGSTKSZ; + stk.ss_size = stack_size; stk.ss_flags = SS_ONSTACK | SS_AUTODISARM; err = sigaltstack(&stk, NULL); if (err) { @@ -161,7 +171,7 @@ int main(void) } } - ustack = mmap(NULL, SIGSTKSZ, PROT_READ | PROT_WRITE, + ustack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0); if (ustack == MAP_FAILED) { ksft_exit_fail_msg("mmap() - %s\n", strerror(errno)); @@ -170,7 +180,7 @@ int main(void) getcontext(&uc); uc.uc_link = NULL; uc.uc_stack.ss_sp = ustack; - uc.uc_stack.ss_size = SIGSTKSZ; + uc.uc_stack.ss_size = stack_size; makecontext(&uc, switch_fn, 0); raise(SIGUSR1); From patchwork Thu Apr 22 04:48:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Chang S. Bae" X-Patchwork-Id: 12217633 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 F20DAC43461 for ; Thu, 22 Apr 2021 04:54:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CF53761435 for ; Thu, 22 Apr 2021 04:54:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232972AbhDVEy4 (ORCPT ); Thu, 22 Apr 2021 00:54:56 -0400 Received: from mga18.intel.com ([134.134.136.126]:45534 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232002AbhDVEyz (ORCPT ); Thu, 22 Apr 2021 00:54:55 -0400 IronPort-SDR: 9mgYFXgs1R6rxY3+P8G2NvGbbT8zd7M1hpAyWpmFk1rcQxP40klWUB4vvlHIJpUCkyF2hBJlNs 6o6AK+lsLoJA== X-IronPort-AV: E=McAfee;i="6200,9189,9961"; a="183311519" X-IronPort-AV: E=Sophos;i="5.82,241,1613462400"; d="scan'208";a="183311519" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Apr 2021 21:54:17 -0700 IronPort-SDR: iuWv1RGultJPAEimWc6O+2MUpUlz62hArWyYV7mZnBXIwqPA0IvaDo5E4DgkG5XCKdzMOaZcDf Wi/6SkKmpyww== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,241,1613462400"; d="scan'208";a="524515422" Received: from chang-linux-3.sc.intel.com ([172.25.66.175]) by fmsmga001.fm.intel.com with ESMTP; 21 Apr 2021 21:54:16 -0700 From: "Chang S. Bae" To: bp@suse.de, tglx@linutronix.de, mingo@kernel.org, luto@kernel.org, x86@kernel.org Cc: len.brown@intel.com, dave.hansen@intel.com, hjl.tools@gmail.com, Dave.Martin@arm.com, jannh@google.com, mpe@ellerman.id.au, carlos@redhat.com, tony.luck@intel.com, ravi.v.shankar@intel.com, libc-alpha@sourceware.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, chang.seok.bae@intel.com, linux-kselftest@vger.kernel.org Subject: [PATCH v8 6/6] selftest/x86/signal: Include test cases for validating sigaltstack Date: Wed, 21 Apr 2021 21:48:56 -0700 Message-Id: <20210422044856.27250-7-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210422044856.27250-1-chang.seok.bae@intel.com> References: <20210422044856.27250-1-chang.seok.bae@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org The test measures the kernel's signal delivery with different (enough vs. insufficient) stack sizes. Signed-off-by: Chang S. Bae Reviewed-by: Len Brown Cc: x86@kernel.org Cc: linux-kselftest@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- Changes from v3: * Revised test messages again (Borislav Petkov) Changes from v2: * Revised test messages (Borislav Petkov) --- tools/testing/selftests/x86/Makefile | 2 +- tools/testing/selftests/x86/sigaltstack.c | 128 ++++++++++++++++++++++ 2 files changed, 129 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/x86/sigaltstack.c diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index 333980375bc7..65bba2ae86ee 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -13,7 +13,7 @@ CAN_BUILD_WITH_NOPIE := $(shell ./check_cc.sh $(CC) trivial_program.c -no-pie) TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt test_mremap_vdso \ check_initial_reg_state sigreturn iopl ioperm \ test_vsyscall mov_ss_trap \ - syscall_arg_fault fsgsbase_restore + syscall_arg_fault fsgsbase_restore sigaltstack TARGETS_C_32BIT_ONLY := entry_from_vm86 test_syscall_vdso unwind_vdso \ test_FCMOV test_FCOMI test_FISTTP \ vdso_restorer diff --git a/tools/testing/selftests/x86/sigaltstack.c b/tools/testing/selftests/x86/sigaltstack.c new file mode 100644 index 000000000000..f689af75e979 --- /dev/null +++ b/tools/testing/selftests/x86/sigaltstack.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* sigaltstack()-enforced minimum stack */ +#define ENFORCED_MINSIGSTKSZ 2048 + +#ifndef AT_MINSIGSTKSZ +# define AT_MINSIGSTKSZ 51 +#endif + +static int nerrs; + +static bool sigalrm_expected; + +static unsigned long at_minstack_size; + +static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *), + int flags) +{ + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_sigaction = handler; + sa.sa_flags = SA_SIGINFO | flags; + sigemptyset(&sa.sa_mask); + if (sigaction(sig, &sa, 0)) + err(1, "sigaction"); +} + +static void clearhandler(int sig) +{ + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = SIG_DFL; + sigemptyset(&sa.sa_mask); + if (sigaction(sig, &sa, 0)) + err(1, "sigaction"); +} + +static int setup_altstack(void *start, unsigned long size) +{ + stack_t ss; + + memset(&ss, 0, sizeof(ss)); + ss.ss_size = size; + ss.ss_sp = start; + + return sigaltstack(&ss, NULL); +} + +static jmp_buf jmpbuf; + +static void sigsegv(int sig, siginfo_t *info, void *ctx_void) +{ + if (sigalrm_expected) { + printf("[FAIL]\tWrong signal delivered: SIGSEGV (expected SIGALRM)."); + nerrs++; + } else { + printf("[OK]\tSIGSEGV signal delivered.\n"); + } + + siglongjmp(jmpbuf, 1); +} + +static void sigalrm(int sig, siginfo_t *info, void *ctx_void) +{ + if (!sigalrm_expected) { + printf("[FAIL]\tWrong signal delivered: SIGALRM (expected SIGSEGV)."); + nerrs++; + } else { + printf("[OK]\tSIGALRM signal delivered.\n"); + } +} + +static void test_sigaltstack(void *altstack, unsigned long size) +{ + if (setup_altstack(altstack, size)) + err(1, "sigaltstack()"); + + sigalrm_expected = (size > at_minstack_size) ? true : false; + + sethandler(SIGSEGV, sigsegv, 0); + sethandler(SIGALRM, sigalrm, SA_ONSTACK); + + if (!sigsetjmp(jmpbuf, 1)) { + printf("[RUN]\tTest an alternate signal stack of %ssufficient size.\n", + sigalrm_expected ? "" : "in"); + printf("\tRaise SIGALRM. %s is expected to be delivered.\n", + sigalrm_expected ? "It" : "SIGSEGV"); + raise(SIGALRM); + } + + clearhandler(SIGALRM); + clearhandler(SIGSEGV); +} + +int main(void) +{ + void *altstack; + + at_minstack_size = getauxval(AT_MINSIGSTKSZ); + + altstack = mmap(NULL, at_minstack_size + SIGSTKSZ, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0); + if (altstack == MAP_FAILED) + err(1, "mmap()"); + + if ((ENFORCED_MINSIGSTKSZ + 1) < at_minstack_size) + test_sigaltstack(altstack, ENFORCED_MINSIGSTKSZ + 1); + + test_sigaltstack(altstack, at_minstack_size + SIGSTKSZ); + + return nerrs == 0 ? 0 : 1; +}