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 ®istered_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)®istered_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