From patchwork Thu May 16 13:59:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 10946671 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BBF6814DB for ; Thu, 16 May 2019 14:00:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A81E4201CB for ; Thu, 16 May 2019 14:00:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9BDAD28B11; Thu, 16 May 2019 14:00:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9305828AFD for ; Thu, 16 May 2019 14:00:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727767AbfEPOAZ (ORCPT ); Thu, 16 May 2019 10:00:25 -0400 Received: from mail-ed1-f65.google.com ([209.85.208.65]:40537 "EHLO mail-ed1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727766AbfEPOAY (ORCPT ); Thu, 16 May 2019 10:00:24 -0400 Received: by mail-ed1-f65.google.com with SMTP id j12so5419737eds.7 for ; Thu, 16 May 2019 07:00:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=brauner.io; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=rBkcy062NYYGXGh6TqicbzBWp7bPNVyN1NSgT1R4iSI=; b=SBA2Nz1vN94S1Ju76/cX3Iq2qNIMZWAqOz9NnQT+n2LMUVlrugi1VxMZtjUVjgcK9k due+GLQjcSxDqrflXBVQFei6HiKpDh7kApiPOrw6kmLMbbPktWHhXiOlumkx7NNcU1pA LDeIIhNfxe2C7tReM/gFpa3dfnLMFAPSO4pBByzIGvcpnd4z6hw8WNUNGVx+Udna4a1I vrAFHOvpdjC0+iCd4SPLgs7ROXDnIxLKx2xOa8zGLomxBC8L5tFYYd0k3jn/gD9zgeYE s1MFUtubfGy+X2H1NMfyabuSW+Ivg+MJT8zM9avfQbS+Qq1WiqQuhEumwvFTKsRnGoVk CFzQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=rBkcy062NYYGXGh6TqicbzBWp7bPNVyN1NSgT1R4iSI=; b=ZZ5vxA+CvlVFlOmS2xdEAbQPdHX2u1jnOtGFbM6GyeEfYJTx4eQWAN6qExaDAK1My7 2bGthL5wi66xksdmANAN+0yloI6bV7eAo701AD/QdyFZg0aOZreRFfWWoEJlmcGxWFJt XuOjVoCdTp0oCpVnTEZZeSHER1Ft9taErp9UaCYHceQPdYsZyJwH+h6gcA8b9IEYPtUE ttiEcmu5vPPjl3M0PMySOjf97ZQXgZGaRznSvRKWhu0y+0+z2I0J1iwil/672Xb0Fbqn Zsa/t2VOh2dUz7AICZBIBieNTQVVWw32Tf8tXCNB8GGAVeYCQ/IiTEWsnlsHWK13cl8T m1Rg== X-Gm-Message-State: APjAAAXpb2dUfCkd0KSyKK+SNrzx2+dD1VBvpIW9NLgaYbzJEcrStAp6 YVmmCuGvRKgryEl+fG9+zvEUuw== X-Google-Smtp-Source: APXvYqwK1uR02XhXcAPkNqh781MathY3wyFgpsh57U9z72OWZ2kjVfoYK27rsXdKaNrGO6FWKr6ZKQ== X-Received: by 2002:a50:b662:: with SMTP id c31mr51477064ede.252.1558015221861; Thu, 16 May 2019 07:00:21 -0700 (PDT) Received: from localhost.localdomain ([193.96.224.243]) by smtp.gmail.com with ESMTPSA id y20sm1093563ejb.40.2019.05.16.07.00.18 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 May 2019 07:00:21 -0700 (PDT) From: Christian Brauner To: jannh@google.com, oleg@redhat.com, viro@zeniv.linux.org.uk, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, arnd@arndb.de Cc: akpm@linux-foundation.org, cyphar@cyphar.com, dhowells@redhat.com, ebiederm@xmission.com, elena.reshetova@intel.com, keescook@chromium.org, luto@amacapital.net, luto@kernel.org, tglx@linutronix.de, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org, joel@joelfernandes.org, dancol@google.com, serge@hallyn.com, Christian Brauner , "Michael Kerrisk (man-pages)" Subject: [PATCH v1 2/2] tests: add pidfd_open() tests Date: Thu, 16 May 2019 15:59:43 +0200 Message-Id: <20190516135944.7205-2-christian@brauner.io> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190516135944.7205-1-christian@brauner.io> References: <20190516135944.7205-1-christian@brauner.io> MIME-Version: 1.0 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This adds testing for the new pidfd_open() syscalls. Specifically, we test: - that no invalid flags can be passed to pidfd_open() - that no invalid pid can be passed to pidfd_open() - that a pidfd can be retrieved with pidfd_open() - that the retrieved pidfd references the correct pid Signed-off-by: Christian Brauner Cc: Arnd Bergmann Cc: "Eric W. Biederman" Cc: Kees Cook Cc: Thomas Gleixner Cc: Jann Horn Cc: David Howells Cc: "Michael Kerrisk (man-pages)" Cc: Andy Lutomirsky Cc: Andrew Morton Cc: Oleg Nesterov Cc: Aleksa Sarai Cc: Linus Torvalds Cc: Al Viro Cc: linux-api@vger.kernel.org --- v1: unchanged --- tools/testing/selftests/pidfd/Makefile | 2 +- tools/testing/selftests/pidfd/pidfd.h | 57 ++++++ .../testing/selftests/pidfd/pidfd_open_test.c | 170 ++++++++++++++++++ tools/testing/selftests/pidfd/pidfd_test.c | 41 +---- 4 files changed, 229 insertions(+), 41 deletions(-) create mode 100644 tools/testing/selftests/pidfd/pidfd.h create mode 100644 tools/testing/selftests/pidfd/pidfd_open_test.c diff --git a/tools/testing/selftests/pidfd/Makefile b/tools/testing/selftests/pidfd/Makefile index deaf8073bc06..b36c0be70848 100644 --- a/tools/testing/selftests/pidfd/Makefile +++ b/tools/testing/selftests/pidfd/Makefile @@ -1,6 +1,6 @@ CFLAGS += -g -I../../../../usr/include/ -TEST_GEN_PROGS := pidfd_test +TEST_GEN_PROGS := pidfd_test pidfd_open_test include ../lib.mk diff --git a/tools/testing/selftests/pidfd/pidfd.h b/tools/testing/selftests/pidfd/pidfd.h new file mode 100644 index 000000000000..8452e910463f --- /dev/null +++ b/tools/testing/selftests/pidfd/pidfd.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __PIDFD_H +#define __PIDFD_H + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest.h" + +/* + * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c + * That means, when it wraps around any pid < 300 will be skipped. + * So we need to use a pid > 300 in order to test recycling. + */ +#define PID_RECYCLE 1000 + +/* + * Define a few custom error codes for the child process to clearly indicate + * what is happening. This way we can tell the difference between a system + * error, a test error, etc. + */ +#define PIDFD_PASS 0 +#define PIDFD_FAIL 1 +#define PIDFD_ERROR 2 +#define PIDFD_SKIP 3 +#define PIDFD_XFAIL 4 + +int wait_for_pid(pid_t pid) +{ + int status, ret; + +again: + ret = waitpid(pid, &status, 0); + if (ret == -1) { + if (errno == EINTR) + goto again; + + return -1; + } + + if (!WIFEXITED(status)) + return -1; + + return WEXITSTATUS(status); +} + + +#endif /* __PIDFD_H */ diff --git a/tools/testing/selftests/pidfd/pidfd_open_test.c b/tools/testing/selftests/pidfd/pidfd_open_test.c new file mode 100644 index 000000000000..9b073c1ac618 --- /dev/null +++ b/tools/testing/selftests/pidfd/pidfd_open_test.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "pidfd.h" +#include "../kselftest.h" + +static inline int sys_pidfd_open(pid_t pid, unsigned int flags) +{ + return syscall(__NR_pidfd_open, pid, flags); +} + +static int safe_int(const char *numstr, int *converted) +{ + char *err = NULL; + long sli; + + errno = 0; + sli = strtol(numstr, &err, 0); + if (errno == ERANGE && (sli == LONG_MAX || sli == LONG_MIN)) + return -ERANGE; + + if (errno != 0 && sli == 0) + return -EINVAL; + + if (err == numstr || *err != '\0') + return -EINVAL; + + if (sli > INT_MAX || sli < INT_MIN) + return -ERANGE; + + *converted = (int)sli; + return 0; +} + +static int char_left_gc(const char *buffer, size_t len) +{ + size_t i; + + for (i = 0; i < len; i++) { + if (buffer[i] == ' ' || + buffer[i] == '\t') + continue; + + return i; + } + + return 0; +} + +static int char_right_gc(const char *buffer, size_t len) +{ + int i; + + for (i = len - 1; i >= 0; i--) { + if (buffer[i] == ' ' || + buffer[i] == '\t' || + buffer[i] == '\n' || + buffer[i] == '\0') + continue; + + return i + 1; + } + + return 0; +} + +static char *trim_whitespace_in_place(char *buffer) +{ + buffer += char_left_gc(buffer, strlen(buffer)); + buffer[char_right_gc(buffer, strlen(buffer))] = '\0'; + return buffer; +} + +static pid_t get_pid_from_fdinfo_file(int pidfd, const char *key, size_t keylen) +{ + int ret; + char path[512]; + FILE *f; + size_t n = 0; + pid_t result = -1; + char *line = NULL; + + snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", pidfd); + + f = fopen(path, "re"); + if (!f) + return -1; + + while (getline(&line, &n, f) != -1) { + char *numstr; + + if (strncmp(line, key, keylen)) + continue; + + numstr = trim_whitespace_in_place(line + 4); + ret = safe_int(numstr, &result); + if (ret < 0) + goto out; + + break; + } + +out: + free(line); + fclose(f); + return result; +} + +int main(int argc, char **argv) +{ + int pidfd = -1, ret = 1; + pid_t pid; + + pidfd = sys_pidfd_open(-1, 0); + if (pidfd >= 0) { + ksft_print_msg( + "%s - succeeded to open pidfd for invalid pid -1\n", + strerror(errno)); + goto on_error; + } + ksft_test_result_pass("do not allow invalid pid test: passed\n"); + ksft_inc_pass_cnt(); + + pidfd = sys_pidfd_open(getpid(), 1); + if (pidfd >= 0) { + ksft_print_msg( + "%s - succeeded to open pidfd with invalid flag value specified\n", + strerror(errno)); + goto on_error; + } + ksft_test_result_pass("do not allow invalid flag test: passed\n"); + ksft_inc_pass_cnt(); + + pidfd = sys_pidfd_open(getpid(), 0); + if (pidfd < 0) { + ksft_print_msg("%s - failed to open pidfd\n", strerror(errno)); + goto on_error; + } + ksft_test_result_pass("open a new pidfd test: passed\n"); + ksft_inc_pass_cnt(); + + pid = get_pid_from_fdinfo_file(pidfd, "Pid:", sizeof("Pid:") - 1); + ksft_print_msg("pidfd %d refers to process with pid %d\n", pidfd, pid); + + ret = 0; + +on_error: + if (pidfd >= 0) + close(pidfd); + + return !ret ? ksft_exit_pass() : ksft_exit_fail(); +} diff --git a/tools/testing/selftests/pidfd/pidfd_test.c b/tools/testing/selftests/pidfd/pidfd_test.c index d59378a93782..f01de87249c9 100644 --- a/tools/testing/selftests/pidfd/pidfd_test.c +++ b/tools/testing/selftests/pidfd/pidfd_test.c @@ -14,6 +14,7 @@ #include #include +#include "pidfd.h" #include "../kselftest.h" static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info, @@ -62,28 +63,6 @@ static int test_pidfd_send_signal_simple_success(void) return 0; } -static int wait_for_pid(pid_t pid) -{ - int status, ret; - -again: - ret = waitpid(pid, &status, 0); - if (ret == -1) { - if (errno == EINTR) - goto again; - - return -1; - } - - if (ret != pid) - goto again; - - if (!WIFEXITED(status)) - return -1; - - return WEXITSTATUS(status); -} - static int test_pidfd_send_signal_exited_fail(void) { int pidfd, ret, saved_errno; @@ -128,13 +107,6 @@ static int test_pidfd_send_signal_exited_fail(void) return 0; } -/* - * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c - * That means, when it wraps around any pid < 300 will be skipped. - * So we need to use a pid > 300 in order to test recycling. - */ -#define PID_RECYCLE 1000 - /* * Maximum number of cycles we allow. This is equivalent to PID_MAX_DEFAULT. * If users set a higher limit or we have cycled PIDFD_MAX_DEFAULT number of @@ -143,17 +115,6 @@ static int test_pidfd_send_signal_exited_fail(void) */ #define PIDFD_MAX_DEFAULT 0x8000 -/* - * Define a few custom error codes for the child process to clearly indicate - * what is happening. This way we can tell the difference between a system - * error, a test error, etc. - */ -#define PIDFD_PASS 0 -#define PIDFD_FAIL 1 -#define PIDFD_ERROR 2 -#define PIDFD_SKIP 3 -#define PIDFD_XFAIL 4 - static int test_pidfd_send_signal_recycled_pid_fail(void) { int i, ret;