1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #pragma once 30 31 #include <poll.h> // For struct pollfd. 32 #include <stdarg.h> 33 #include <stdlib.h> 34 #include <sys/select.h> // For struct fd_set. 35 36 #include <async_safe/log.h> 37 38 static inline __noreturn void __fortify_fatal(const char* fmt, ...) { 39 va_list args; 40 va_start(args, fmt); 41 async_safe_fatal_va_list("FORTIFY", fmt, args); 42 va_end(args); 43 abort(); 44 } 45 46 // 47 // Common helpers. 48 // 49 50 static inline void __check_fd_set(const char* fn, int fd, size_t set_size) { 51 if (__predict_false(fd < 0)) { 52 __fortify_fatal("%s: file descriptor %d < 0", fn, fd); 53 } 54 if (__predict_false(fd >= FD_SETSIZE)) { 55 __fortify_fatal("%s: file descriptor %d >= FD_SETSIZE %zu", fn, fd, set_size); 56 } 57 if (__predict_false(set_size < sizeof(fd_set))) { 58 __fortify_fatal("%s: set size %zu is too small to be an fd_set", fn, set_size); 59 } 60 } 61 62 static inline void __check_pollfd_array(const char* fn, size_t fds_size, nfds_t fd_count) { 63 size_t pollfd_array_length = fds_size / sizeof(pollfd); 64 if (__predict_false(pollfd_array_length < fd_count)) { 65 __fortify_fatal("%s: %zu-element pollfd array too small for %u fds", 66 fn, pollfd_array_length, fd_count); 67 } 68 } 69 70 static inline void __check_count(const char* fn, const char* identifier, size_t value) { 71 if (__predict_false(value > SSIZE_MAX)) { 72 __fortify_fatal("%s: %s %zu > SSIZE_MAX", fn, identifier, value); 73 } 74 } 75 76 static inline void __check_buffer_access(const char* fn, const char* action, 77 size_t claim, size_t actual) { 78 if (__predict_false(claim > actual)) { 79 __fortify_fatal("%s: prevented %zu-byte %s %zu-byte buffer", fn, claim, action, actual); 80 } 81 } 82
