1//===-- sanitizer_linux.h ---------------------------------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// Linux-specific syscall wrappers and classes. 11// 12//===----------------------------------------------------------------------===// 13#ifndef SANITIZER_LINUX_H 14#define SANITIZER_LINUX_H 15 16#include "sanitizer_platform.h" 17#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \ 18 SANITIZER_OPENBSD || SANITIZER_SOLARIS 19#include "sanitizer_common.h" 20#include "sanitizer_internal_defs.h" 21#include "sanitizer_platform_limits_freebsd.h" 22#include "sanitizer_platform_limits_netbsd.h" 23#include "sanitizer_platform_limits_openbsd.h" 24#include "sanitizer_platform_limits_posix.h" 25#include "sanitizer_platform_limits_solaris.h" 26#include "sanitizer_posix.h" 27 28struct link_map; // Opaque type returned by dlopen(). 29 30namespace __sanitizer { 31// Dirent structure for getdents(). Note that this structure is different from 32// the one in <dirent.h>, which is used by readdir(). 33struct linux_dirent; 34 35struct ProcSelfMapsBuff { 36 char *data; 37 uptr mmaped_size; 38 uptr len; 39}; 40 41struct MemoryMappingLayoutData { 42 ProcSelfMapsBuff proc_self_maps; 43 const char *current; 44}; 45 46void ReadProcMaps(ProcSelfMapsBuff *proc_maps); 47 48// Syscall wrappers. 49uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count); 50uptr internal_sigaltstack(const void* ss, void* oss); 51uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set, 52 __sanitizer_sigset_t *oldset); 53uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp); 54 55// Linux-only syscalls. 56#if SANITIZER_LINUX 57uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5); 58// Used only by sanitizer_stoptheworld. Signal handlers that are actually used 59// (like the process-wide error reporting SEGV handler) must use 60// internal_sigaction instead. 61int internal_sigaction_norestorer(int signum, const void *act, void *oldact); 62#if (defined(__x86_64__) || SANITIZER_MIPS64) && !SANITIZER_GO 63// Uses a raw system call to avoid interceptors. 64int internal_sigaction_syscall(int signum, const void *act, void *oldact); 65#endif 66void internal_sigdelset(__sanitizer_sigset_t *set, int signum); 67#if defined(__x86_64__) || defined(__mips__) || defined(__aarch64__) \ 68 || defined(__powerpc64__) || defined(__s390__) || defined(__i386__) \ 69 || defined(__arm__) 70uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg, 71 int *parent_tidptr, void *newtls, int *child_tidptr); 72#endif 73#elif SANITIZER_FREEBSD 74void internal_sigdelset(__sanitizer_sigset_t *set, int signum); 75#endif // SANITIZER_LINUX 76 77// This class reads thread IDs from /proc/<pid>/task using only syscalls. 78class ThreadLister { 79 public: 80 explicit ThreadLister(pid_t pid); 81 ~ThreadLister(); 82 enum Result { 83 Error, 84 Incomplete, 85 Ok, 86 }; 87 Result ListThreads(InternalMmapVector<tid_t> *threads); 88 89 private: 90 bool IsAlive(int tid); 91 92 pid_t pid_; 93 int descriptor_ = -1; 94 InternalMmapVector<char> buffer_; 95}; 96 97// Exposed for testing. 98uptr ThreadDescriptorSize(); 99uptr ThreadSelf(); 100uptr ThreadSelfOffset(); 101 102// Matches a library's file name against a base name (stripping path and version 103// information). 104bool LibraryNameIs(const char *full_name, const char *base_name); 105 106// Call cb for each region mapped by map. 107void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)); 108 109#if SANITIZER_ANDROID 110 111#if defined(__aarch64__) 112# define __get_tls() \ 113 ({ void** __v; __asm__("mrs %0, tpidr_el0" : "=r"(__v)); __v; }) 114#elif defined(__arm__) 115# define __get_tls() \ 116 ({ void** __v; __asm__("mrc p15, 0, %0, c13, c0, 3" : "=r"(__v)); __v; }) 117#elif defined(__mips__) 118// On mips32r1, this goes via a kernel illegal instruction trap that's 119// optimized for v1. 120# define __get_tls() \ 121 ({ register void** __v asm("v1"); \ 122 __asm__(".set push\n" \ 123 ".set mips32r2\n" \ 124 "rdhwr %0,$29\n" \ 125 ".set pop\n" : "=r"(__v)); \ 126 __v; }) 127#elif defined(__i386__) 128# define __get_tls() \ 129 ({ void** __v; __asm__("movl %%gs:0, %0" : "=r"(__v)); __v; }) 130#elif defined(__x86_64__) 131# define __get_tls() \ 132 ({ void** __v; __asm__("mov %%fs:0, %0" : "=r"(__v)); __v; }) 133#else 134#error "Unsupported architecture." 135#endif 136 137// The Android Bionic team has allocated a TLS slot for sanitizers starting 138// with Q, given that Android currently doesn't support ELF TLS. It is used to 139// store sanitizer thread specific data. 140static const int TLS_SLOT_SANITIZER = 6; 141 142ALWAYS_INLINE uptr *get_android_tls_ptr() { 143 return reinterpret_cast<uptr *>(&__get_tls()[TLS_SLOT_SANITIZER]); 144} 145 146#endif // SANITIZER_ANDROID 147 148} // namespace __sanitizer 149 150#endif 151#endif // SANITIZER_LINUX_H 152