1 //===-- sanitizer_linux.h ---------------------------------------*- C++ -*-===//
2 //
3 // This file is distributed under the University of Illinois Open Source
4 // License. See LICENSE.TXT for details.
5 //
6 //===----------------------------------------------------------------------===//
7 //
8 // Linux-specific syscall wrappers and classes.
9 //
10 //===----------------------------------------------------------------------===//
11 #ifndef SANITIZER_LINUX_H
12 #define SANITIZER_LINUX_H
13
14 #include "sanitizer_platform.h"
15 #if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \
16 SANITIZER_OPENBSD || SANITIZER_SOLARIS
17 #include "sanitizer_common.h"
18 #include "sanitizer_internal_defs.h"
19 #include "sanitizer_platform_limits_netbsd.h"
20 #include "sanitizer_platform_limits_openbsd.h"
21 #include "sanitizer_platform_limits_posix.h"
22 #include "sanitizer_platform_limits_solaris.h"
23 #include "sanitizer_posix.h"
24
25 struct link_map; // Opaque type returned by dlopen().
26
27 namespace __sanitizer {
28 // Dirent structure for getdents(). Note that this structure is different from
29 // the one in <dirent.h>, which is used by readdir().
30 struct linux_dirent;
31
32 struct ProcSelfMapsBuff {
33 char *data;
34 uptr mmaped_size;
35 uptr len;
36 };
37
38 struct MemoryMappingLayoutData {
39 ProcSelfMapsBuff proc_self_maps;
40 const char *current;
41 };
42
43 void ReadProcMaps(ProcSelfMapsBuff *proc_maps);
44
45 // Syscall wrappers.
46 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
47 uptr internal_sigaltstack(const void* ss, void* oss);
48 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
49 __sanitizer_sigset_t *oldset);
50 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp);
51
52 // Linux-only syscalls.
53 #if SANITIZER_LINUX
54 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5);
55 // Used only by sanitizer_stoptheworld. Signal handlers that are actually used
56 // (like the process-wide error reporting SEGV handler) must use
57 // internal_sigaction instead.
58 int internal_sigaction_norestorer(int signum, const void *act, void *oldact);
59 #if (defined(__x86_64__) || SANITIZER_MIPS64) && !SANITIZER_GO
60 // Uses a raw system call to avoid interceptors.
61 int internal_sigaction_syscall(int signum, const void *act, void *oldact);
62 #endif
63 void internal_sigdelset(__sanitizer_sigset_t *set, int signum);
64 #if defined(__x86_64__) || defined(__mips__) || defined(__aarch64__) \
65 || defined(__powerpc64__) || defined(__s390__) || defined(__i386__) \
66 || defined(__arm__)
67 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
68 int *parent_tidptr, void *newtls, int *child_tidptr);
69 #endif
70 #elif SANITIZER_FREEBSD
71 void internal_sigdelset(__sanitizer_sigset_t *set, int signum);
72 #elif SANITIZER_NETBSD
73 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5);
74 #endif // SANITIZER_LINUX
75
76 #ifdef SANITIZER_NETBSD
77 void internal_sigdelset(__sanitizer_sigset_t *set, int signum);
78 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg);
79 #endif
80
81 // This class reads thread IDs from /proc/<pid>/task using only syscalls.
82 class ThreadLister {
83 public:
84 explicit ThreadLister(pid_t pid);
85 ~ThreadLister();
86 enum Result {
87 Error,
88 Incomplete,
89 Ok,
90 };
91 Result ListThreads(InternalMmapVector<tid_t> *threads);
92
93 private:
94 bool IsAlive(int tid);
95
96 pid_t pid_;
97 int descriptor_ = -1;
98 InternalMmapVector<char> buffer_;
99 };
100
101 // Exposed for testing.
102 uptr ThreadDescriptorSize();
103 uptr ThreadSelf();
104 uptr ThreadSelfOffset();
105
106 // Matches a library's file name against a base name (stripping path and version
107 // information).
108 bool LibraryNameIs(const char *full_name, const char *base_name);
109
110 // Call cb for each region mapped by map.
111 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr));
112
113 #if SANITIZER_ANDROID
114
115 #if defined(__aarch64__)
116 # define __get_tls() \
117 ({ void** __v; __asm__("mrs %0, tpidr_el0" : "=r"(__v)); __v; })
118 #elif defined(__arm__)
119 # define __get_tls() \
120 ({ void** __v; __asm__("mrc p15, 0, %0, c13, c0, 3" : "=r"(__v)); __v; })
121 #elif defined(__mips__)
122 // On mips32r1, this goes via a kernel illegal instruction trap that's
123 // optimized for v1.
124 # define __get_tls() \
125 ({ register void** __v asm("v1"); \
126 __asm__(".set push\n" \
127 ".set mips32r2\n" \
128 "rdhwr %0,$29\n" \
129 ".set pop\n" : "=r"(__v)); \
130 __v; })
131 #elif defined(__i386__)
132 # define __get_tls() \
133 ({ void** __v; __asm__("movl %%gs:0, %0" : "=r"(__v)); __v; })
134 #elif defined(__x86_64__)
135 # define __get_tls() \
136 ({ void** __v; __asm__("mov %%fs:0, %0" : "=r"(__v)); __v; })
137 #else
138 #error "Unsupported architecture."
139 #endif
140
141 // The Android Bionic team has allocated a TLS slot for TSan starting with N,
142 // given that Android currently doesn't support ELF TLS. It is used to store
143 // Sanitizers thread specific data.
144 static const int TLS_SLOT_TSAN = 8;
145
get_android_tls_ptr()146 ALWAYS_INLINE uptr *get_android_tls_ptr() {
147 return reinterpret_cast<uptr *>(&__get_tls()[TLS_SLOT_TSAN]);
148 }
149
150 #endif // SANITIZER_ANDROID
151
152 } // namespace __sanitizer
153
154 #endif
155 #endif // SANITIZER_LINUX_H
156