blob: 910703d8b2939446815411304f696e2d2bf58649 [file] [log] [blame]
//===-- sanitizer_linux.h ---------------------------------------*- C++ -*-===//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// Linux-specific syscall wrappers and classes.
#include "sanitizer_platform.h"
#include "sanitizer_common.h"
#include "sanitizer_internal_defs.h"
#include "sanitizer_platform_limits_netbsd.h"
#include "sanitizer_platform_limits_posix.h"
#include "sanitizer_posix.h"
struct link_map; // Opaque type returned by dlopen().
namespace __sanitizer {
// Dirent structure for getdents(). Note that this structure is different from
// the one in <dirent.h>, which is used by readdir().
struct linux_dirent;
struct ProcSelfMapsBuff {
char *data;
uptr mmaped_size;
uptr len;
struct MemoryMappingLayoutData {
ProcSelfMapsBuff proc_self_maps;
const char *current;
void ReadProcMaps(ProcSelfMapsBuff *proc_maps);
// Syscall wrappers.
uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
uptr internal_sigaltstack(const void* ss, void* oss);
uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
__sanitizer_sigset_t *oldset);
// Linux-only syscalls.
uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5);
// Used only by sanitizer_stoptheworld. Signal handlers that are actually used
// (like the process-wide error reporting SEGV handler) must use
// internal_sigaction instead.
int internal_sigaction_norestorer(int signum, const void *act, void *oldact);
#if (defined(__x86_64__) || SANITIZER_MIPS64) && !SANITIZER_GO
// Uses a raw system call to avoid interceptors.
int internal_sigaction_syscall(int signum, const void *act, void *oldact);
void internal_sigdelset(__sanitizer_sigset_t *set, int signum);
#if defined(__x86_64__) || defined(__mips__) || defined(__aarch64__) \
|| defined(__powerpc64__) || defined(__s390__) || defined(__i386__) \
|| defined(__arm__)
uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
int *parent_tidptr, void *newtls, int *child_tidptr);
// This class reads thread IDs from /proc/<pid>/task using only syscalls.
class ThreadLister {
explicit ThreadLister(int pid);
// GetNextTID returns -1 if the list of threads is exhausted, or if there has
// been an error.
int GetNextTID();
void Reset();
bool error();
bool GetDirectoryEntries();
int pid_;
int descriptor_;
InternalScopedBuffer<char> buffer_;
bool error_;
struct linux_dirent* entry_;
int bytes_read_;
// Exposed for testing.
uptr ThreadDescriptorSize();
uptr ThreadSelf();
uptr ThreadSelfOffset();
// Matches a library's file name against a base name (stripping path and version
// information).
bool LibraryNameIs(const char *full_name, const char *base_name);
// Call cb for each region mapped by map.
void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr));
#if defined(__aarch64__)
# define __get_tls() \
({ void** __v; __asm__("mrs %0, tpidr_el0" : "=r"(__v)); __v; })
#elif defined(__arm__)
# define __get_tls() \
({ void** __v; __asm__("mrc p15, 0, %0, c13, c0, 3" : "=r"(__v)); __v; })
#elif defined(__mips__)
// On mips32r1, this goes via a kernel illegal instruction trap that's
// optimized for v1.
# define __get_tls() \
({ register void** __v asm("v1"); \
__asm__(".set push\n" \
".set mips32r2\n" \
"rdhwr %0,$29\n" \
".set pop\n" : "=r"(__v)); \
__v; })
#elif defined(__i386__)
# define __get_tls() \
({ void** __v; __asm__("movl %%gs:0, %0" : "=r"(__v)); __v; })
#elif defined(__x86_64__)
# define __get_tls() \
({ void** __v; __asm__("mov %%fs:0, %0" : "=r"(__v)); __v; })
#error "Unsupported architecture."
// The Android Bionic team has allocated a TLS slot for TSan starting with N,
// given that Android currently doesn't support ELF TLS. It is used to store
// Sanitizers thread specific data.
static const int TLS_SLOT_TSAN = 8;
ALWAYS_INLINE uptr *get_android_tls_ptr() {
return reinterpret_cast<uptr *>(&__get_tls()[TLS_SLOT_TSAN]);
} // namespace __sanitizer