xref: /freebsd-src/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_external.cpp (revision 68d75eff68281c1b445e3010bb975eae07aac225)
1*68d75effSDimitry Andric //===-- tsan_external.cpp -------------------------------------------------===//
2*68d75effSDimitry Andric //
3*68d75effSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*68d75effSDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*68d75effSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*68d75effSDimitry Andric //
7*68d75effSDimitry Andric //===----------------------------------------------------------------------===//
8*68d75effSDimitry Andric //
9*68d75effSDimitry Andric // This file is a part of ThreadSanitizer (TSan), a race detector.
10*68d75effSDimitry Andric //
11*68d75effSDimitry Andric //===----------------------------------------------------------------------===//
12*68d75effSDimitry Andric #include "tsan_rtl.h"
13*68d75effSDimitry Andric #include "tsan_interceptors.h"
14*68d75effSDimitry Andric 
15*68d75effSDimitry Andric namespace __tsan {
16*68d75effSDimitry Andric 
17*68d75effSDimitry Andric #define CALLERPC ((uptr)__builtin_return_address(0))
18*68d75effSDimitry Andric 
19*68d75effSDimitry Andric struct TagData {
20*68d75effSDimitry Andric   const char *object_type;
21*68d75effSDimitry Andric   const char *header;
22*68d75effSDimitry Andric };
23*68d75effSDimitry Andric 
24*68d75effSDimitry Andric static TagData registered_tags[kExternalTagMax] = {
25*68d75effSDimitry Andric   {},
26*68d75effSDimitry Andric   {"Swift variable", "Swift access race"},
27*68d75effSDimitry Andric };
28*68d75effSDimitry Andric static atomic_uint32_t used_tags{kExternalTagFirstUserAvailable};
29*68d75effSDimitry Andric static TagData *GetTagData(uptr tag) {
30*68d75effSDimitry Andric   // Invalid/corrupted tag?  Better return NULL and let the caller deal with it.
31*68d75effSDimitry Andric   if (tag >= atomic_load(&used_tags, memory_order_relaxed)) return nullptr;
32*68d75effSDimitry Andric   return &registered_tags[tag];
33*68d75effSDimitry Andric }
34*68d75effSDimitry Andric 
35*68d75effSDimitry Andric const char *GetObjectTypeFromTag(uptr tag) {
36*68d75effSDimitry Andric   TagData *tag_data = GetTagData(tag);
37*68d75effSDimitry Andric   return tag_data ? tag_data->object_type : nullptr;
38*68d75effSDimitry Andric }
39*68d75effSDimitry Andric 
40*68d75effSDimitry Andric const char *GetReportHeaderFromTag(uptr tag) {
41*68d75effSDimitry Andric   TagData *tag_data = GetTagData(tag);
42*68d75effSDimitry Andric   return tag_data ? tag_data->header : nullptr;
43*68d75effSDimitry Andric }
44*68d75effSDimitry Andric 
45*68d75effSDimitry Andric void InsertShadowStackFrameForTag(ThreadState *thr, uptr tag) {
46*68d75effSDimitry Andric   FuncEntry(thr, (uptr)&registered_tags[tag]);
47*68d75effSDimitry Andric }
48*68d75effSDimitry Andric 
49*68d75effSDimitry Andric uptr TagFromShadowStackFrame(uptr pc) {
50*68d75effSDimitry Andric   uptr tag_count = atomic_load(&used_tags, memory_order_relaxed);
51*68d75effSDimitry Andric   void *pc_ptr = (void *)pc;
52*68d75effSDimitry Andric   if (pc_ptr < GetTagData(0) || pc_ptr > GetTagData(tag_count - 1))
53*68d75effSDimitry Andric     return 0;
54*68d75effSDimitry Andric   return (TagData *)pc_ptr - GetTagData(0);
55*68d75effSDimitry Andric }
56*68d75effSDimitry Andric 
57*68d75effSDimitry Andric #if !SANITIZER_GO
58*68d75effSDimitry Andric 
59*68d75effSDimitry Andric typedef void(*AccessFunc)(ThreadState *, uptr, uptr, int);
60*68d75effSDimitry Andric void ExternalAccess(void *addr, void *caller_pc, void *tag, AccessFunc access) {
61*68d75effSDimitry Andric   CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
62*68d75effSDimitry Andric   ThreadState *thr = cur_thread();
63*68d75effSDimitry Andric   if (caller_pc) FuncEntry(thr, (uptr)caller_pc);
64*68d75effSDimitry Andric   InsertShadowStackFrameForTag(thr, (uptr)tag);
65*68d75effSDimitry Andric   bool in_ignored_lib;
66*68d75effSDimitry Andric   if (!caller_pc || !libignore()->IsIgnored((uptr)caller_pc, &in_ignored_lib)) {
67*68d75effSDimitry Andric     access(thr, CALLERPC, (uptr)addr, kSizeLog1);
68*68d75effSDimitry Andric   }
69*68d75effSDimitry Andric   FuncExit(thr);
70*68d75effSDimitry Andric   if (caller_pc) FuncExit(thr);
71*68d75effSDimitry Andric }
72*68d75effSDimitry Andric 
73*68d75effSDimitry Andric extern "C" {
74*68d75effSDimitry Andric SANITIZER_INTERFACE_ATTRIBUTE
75*68d75effSDimitry Andric void *__tsan_external_register_tag(const char *object_type) {
76*68d75effSDimitry Andric   uptr new_tag = atomic_fetch_add(&used_tags, 1, memory_order_relaxed);
77*68d75effSDimitry Andric   CHECK_LT(new_tag, kExternalTagMax);
78*68d75effSDimitry Andric   GetTagData(new_tag)->object_type = internal_strdup(object_type);
79*68d75effSDimitry Andric   char header[127] = {0};
80*68d75effSDimitry Andric   internal_snprintf(header, sizeof(header), "race on %s", object_type);
81*68d75effSDimitry Andric   GetTagData(new_tag)->header = internal_strdup(header);
82*68d75effSDimitry Andric   return (void *)new_tag;
83*68d75effSDimitry Andric }
84*68d75effSDimitry Andric 
85*68d75effSDimitry Andric SANITIZER_INTERFACE_ATTRIBUTE
86*68d75effSDimitry Andric void __tsan_external_register_header(void *tag, const char *header) {
87*68d75effSDimitry Andric   CHECK_GE((uptr)tag, kExternalTagFirstUserAvailable);
88*68d75effSDimitry Andric   CHECK_LT((uptr)tag, kExternalTagMax);
89*68d75effSDimitry Andric   atomic_uintptr_t *header_ptr =
90*68d75effSDimitry Andric       (atomic_uintptr_t *)&GetTagData((uptr)tag)->header;
91*68d75effSDimitry Andric   header = internal_strdup(header);
92*68d75effSDimitry Andric   char *old_header =
93*68d75effSDimitry Andric       (char *)atomic_exchange(header_ptr, (uptr)header, memory_order_seq_cst);
94*68d75effSDimitry Andric   if (old_header) internal_free(old_header);
95*68d75effSDimitry Andric }
96*68d75effSDimitry Andric 
97*68d75effSDimitry Andric SANITIZER_INTERFACE_ATTRIBUTE
98*68d75effSDimitry Andric void __tsan_external_assign_tag(void *addr, void *tag) {
99*68d75effSDimitry Andric   CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
100*68d75effSDimitry Andric   Allocator *a = allocator();
101*68d75effSDimitry Andric   MBlock *b = nullptr;
102*68d75effSDimitry Andric   if (a->PointerIsMine((void *)addr)) {
103*68d75effSDimitry Andric     void *block_begin = a->GetBlockBegin((void *)addr);
104*68d75effSDimitry Andric     if (block_begin) b = ctx->metamap.GetBlock((uptr)block_begin);
105*68d75effSDimitry Andric   }
106*68d75effSDimitry Andric   if (b) {
107*68d75effSDimitry Andric     b->tag = (uptr)tag;
108*68d75effSDimitry Andric   }
109*68d75effSDimitry Andric }
110*68d75effSDimitry Andric 
111*68d75effSDimitry Andric SANITIZER_INTERFACE_ATTRIBUTE
112*68d75effSDimitry Andric void __tsan_external_read(void *addr, void *caller_pc, void *tag) {
113*68d75effSDimitry Andric   ExternalAccess(addr, caller_pc, tag, MemoryRead);
114*68d75effSDimitry Andric }
115*68d75effSDimitry Andric 
116*68d75effSDimitry Andric SANITIZER_INTERFACE_ATTRIBUTE
117*68d75effSDimitry Andric void __tsan_external_write(void *addr, void *caller_pc, void *tag) {
118*68d75effSDimitry Andric   ExternalAccess(addr, caller_pc, tag, MemoryWrite);
119*68d75effSDimitry Andric }
120*68d75effSDimitry Andric }  // extern "C"
121*68d75effSDimitry Andric 
122*68d75effSDimitry Andric #endif  // !SANITIZER_GO
123*68d75effSDimitry Andric 
124*68d75effSDimitry Andric }  // namespace __tsan
125