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
28 struct link_map; // Opaque type returned by dlopen().
29
30 namespace __sanitizer {
31 // Dirent structure for getdents(). Note that this structure is different from
32 // the one in <dirent.h>, which is used by readdir().
33 struct linux_dirent;
34
35 struct ProcSelfMapsBuff {
36 char *data;
37 uptr mmaped_size;
38 uptr len;
39 };
40
41 struct MemoryMappingLayoutData {
42 ProcSelfMapsBuff proc_self_maps;
43 const char *current;
44 };
45
46 void ReadProcMaps(ProcSelfMapsBuff *proc_maps);
47
48 // Syscall wrappers.
49 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
50 uptr internal_sigaltstack(const void* ss, void* oss);
51 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
52 __sanitizer_sigset_t *oldset);
53 uptr internal_clock_gettime(__sanitizer_clockid_t clk_id, void *tp);
54
55 // Linux-only syscalls.
56 #if SANITIZER_LINUX
57 uptr 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.
61 int 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.
64 int internal_sigaction_syscall(int signum, const void *act, void *oldact);
65 #endif
66 void 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__)
70 uptr 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
74 void 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.
78 class 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.
98 uptr ThreadDescriptorSize();
99 uptr ThreadSelf();
100 uptr ThreadSelfOffset();
101
102 // Matches a library's file name against a base name (stripping path and version
103 // information).
104 bool LibraryNameIs(const char *full_name, const char *base_name);
105
106 // Call cb for each region mapped by map.
107 void 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.
140 static const int TLS_SLOT_SANITIZER = 6;
141
get_android_tls_ptr()142 ALWAYS_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