llvm-project/compiler-rt/lib/tsan/rtl/tsan_rtl_report.cc

355 lines
11 KiB
C++

//===-- tsan_rtl.cc ---------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of ThreadSanitizer (TSan), a race detector.
//
//===----------------------------------------------------------------------===//
#include "tsan_platform.h"
#include "tsan_rtl.h"
#include "tsan_suppressions.h"
#include "tsan_symbolize.h"
#include "tsan_report.h"
#include "tsan_sync.h"
#include "tsan_mman.h"
#include "tsan_flags.h"
#include "tsan_placement_new.h"
namespace __tsan {
// Can be overriden by an application/test to intercept reports.
bool WEAK OnReport(const ReportDesc *rep, bool suppressed) {
(void)rep;
return suppressed;
}
static void StackStripMain(ReportStack *stack) {
ReportStack *last_frame = 0;
ReportStack *last_frame2 = 0;
const char *prefix = "interception_wrap_";
uptr prefix_len = internal_strlen(prefix);
const char *path_prefix = flags()->strip_path_prefix;
uptr path_prefix_len = internal_strlen(path_prefix);
for (ReportStack *ent = stack; ent; ent = ent->next) {
if (ent->func && 0 == internal_strncmp(ent->func, prefix, prefix_len))
ent->func += prefix_len;
if (ent->file && 0 == internal_strncmp(ent->file, path_prefix,
path_prefix_len))
ent->file += path_prefix_len;
if (ent->file && ent->file[0] == '.' && ent->file[1] == '/')
ent->file += 2;
last_frame2 = last_frame;
last_frame = ent;
}
if (last_frame2 == 0)
return;
const char *last = last_frame->func;
const char *last2 = last_frame2->func;
// Strip frame above 'main'
if (last2 && 0 == internal_strcmp(last2, "main")) {
last_frame2->next = 0;
// Strip our internal thread start routine.
} else if (last && 0 == internal_strcmp(last, "__tsan_thread_start_func")) {
last_frame2->next = 0;
// Strip global ctors init.
} else if (last && 0 == internal_strcmp(last, "__do_global_ctors_aux")) {
last_frame2->next = 0;
// If both are 0, then we probably just failed to symbolize.
} else if (last || last2) {
// Ensure that we recovered stack completely. Trimmed stack
// can actually happen if we do not instrument some code,
// so it's only a DCHECK. However we must try hard to not miss it
// due to our fault.
Printf("Bottom stack frame of stack %lx is missed\n", stack->pc);
}
}
static ReportStack *SymbolizeStack(const StackTrace& trace) {
if (trace.IsEmpty())
return 0;
ReportStack *stack = 0;
for (uptr si = 0; si < trace.Size(); si++) {
// We obtain the return address, that is, address of the next instruction,
// so offset it by 1 byte.
bool is_last = (si == trace.Size() - 1);
ReportStack *ent = SymbolizeCode(trace.Get(si) - !is_last);
CHECK_NE(ent, 0);
ReportStack *last = ent;
while (last->next) {
last->pc += !is_last;
last = last->next;
}
last->pc += !is_last;
last->next = stack;
stack = ent;
}
StackStripMain(stack);
return stack;
}
ScopedReport::ScopedReport(ReportType typ) {
ctx_ = CTX();
void *mem = internal_alloc(MBlockReport, sizeof(ReportDesc));
rep_ = new(mem) ReportDesc;
rep_->typ = typ;
ctx_->report_mtx.Lock();
}
ScopedReport::~ScopedReport() {
ctx_->report_mtx.Unlock();
rep_->~ReportDesc();
internal_free(rep_);
}
void ScopedReport::AddStack(const StackTrace *stack) {
ReportStack **rs = rep_->stacks.PushBack();
*rs = SymbolizeStack(*stack);
}
void ScopedReport::AddMemoryAccess(uptr addr, Shadow s,
const StackTrace *stack) {
void *mem = internal_alloc(MBlockReportMop, sizeof(ReportMop));
ReportMop *mop = new(mem) ReportMop;
rep_->mops.PushBack(mop);
mop->tid = s.tid();
mop->addr = addr + s.addr0();
mop->size = s.size();
mop->write = s.is_write();
mop->nmutex = 0;
mop->stack = SymbolizeStack(*stack);
}
void ScopedReport::AddThread(const ThreadContext *tctx) {
void *mem = internal_alloc(MBlockReportThread, sizeof(ReportThread));
ReportThread *rt = new(mem) ReportThread();
rep_->threads.PushBack(rt);
rt->id = tctx->tid;
rt->running = (tctx->status == ThreadStatusRunning);
rt->stack = SymbolizeStack(tctx->creation_stack);
}
void ScopedReport::AddMutex(const SyncVar *s) {
void *mem = internal_alloc(MBlockReportMutex, sizeof(ReportMutex));
ReportMutex *rm = new(mem) ReportMutex();
rep_->mutexes.PushBack(rm);
rm->id = 42;
rm->stack = SymbolizeStack(s->creation_stack);
}
void ScopedReport::AddLocation(uptr addr, uptr size) {
ReportStack *symb = SymbolizeData(addr);
if (symb) {
void *mem = internal_alloc(MBlockReportLoc, sizeof(ReportLocation));
ReportLocation *loc = new(mem) ReportLocation();
rep_->locs.PushBack(loc);
loc->type = ReportLocationGlobal;
loc->addr = addr;
loc->size = size;
loc->tid = 0;
loc->name = symb->func;
loc->file = symb->file;
loc->line = symb->line;
loc->stack = 0;
internal_free(symb);
}
}
const ReportDesc *ScopedReport::GetReport() const {
return rep_;
}
static void RestoreStack(int tid, const u64 epoch, StackTrace *stk) {
ThreadContext *tctx = CTX()->threads[tid];
if (tctx == 0)
return;
Trace* trace = 0;
if (tctx->status == ThreadStatusRunning) {
CHECK(tctx->thr);
trace = &tctx->thr->trace;
} else if (tctx->status == ThreadStatusFinished
|| tctx->status == ThreadStatusDead) {
trace = &tctx->dead_info.trace;
} else {
return;
}
Lock l(&trace->mtx);
const int partidx = (epoch / (kTraceSize / kTraceParts)) % kTraceParts;
TraceHeader* hdr = &trace->headers[partidx];
if (epoch < hdr->epoch0)
return;
const u64 eend = epoch % kTraceSize;
const u64 ebegin = eend / kTracePartSize * kTracePartSize;
DPrintf("#%d: RestoreStack epoch=%llu ebegin=%llu eend=%llu partidx=%d\n",
tid, epoch, ebegin, eend, partidx);
InternalScopedBuf<uptr> stack(1024); // FIXME: de-hardcode 1024
for (uptr i = 0; i < hdr->stack0.Size(); i++) {
stack[i] = hdr->stack0.Get(i);
DPrintf2(" #%02lu: pc=%lx\n", i, stack[i]);
}
uptr pos = hdr->stack0.Size();
for (uptr i = ebegin; i <= eend; i++) {
Event ev = trace->events[i];
EventType typ = (EventType)(ev >> 61);
uptr pc = (uptr)(ev & 0xffffffffffffull);
DPrintf2(" %lu typ=%d pc=%lx\n", i, typ, pc);
if (typ == EventTypeMop) {
stack[pos] = pc;
} else if (typ == EventTypeFuncEnter) {
stack[pos++] = pc;
} else if (typ == EventTypeFuncExit) {
// Since we have full stacks, this should never happen.
DCHECK_GT(pos, 0);
if (pos > 0)
pos--;
}
for (uptr j = 0; j <= pos; j++)
DPrintf2(" #%lu: %lx\n", j, stack[j]);
}
if (pos == 0 && stack[0] == 0)
return;
pos++;
stk->Init(stack, pos);
}
static bool HandleRacyStacks(ThreadState *thr, const StackTrace (&traces)[2],
uptr addr_min, uptr addr_max) {
Context *ctx = CTX();
bool equal_stack = false;
RacyStacks hash = {};
if (flags()->suppress_equal_stacks) {
hash.hash[0] = md5_hash(traces[0].Begin(), traces[0].Size() * sizeof(uptr));
hash.hash[1] = md5_hash(traces[1].Begin(), traces[1].Size() * sizeof(uptr));
for (uptr i = 0; i < ctx->racy_stacks.Size(); i++) {
if (hash == ctx->racy_stacks[i]) {
DPrintf("ThreadSanitizer: suppressing report as doubled (stack)\n");
equal_stack = true;
break;
}
}
}
bool equal_address = false;
RacyAddress ra0 = {addr_min, addr_max};
if (flags()->suppress_equal_addresses) {
for (uptr i = 0; i < ctx->racy_addresses.Size(); i++) {
RacyAddress ra2 = ctx->racy_addresses[i];
uptr maxbeg = max(ra0.addr_min, ra2.addr_min);
uptr minend = min(ra0.addr_max, ra2.addr_max);
if (maxbeg < minend) {
DPrintf("ThreadSanitizer: suppressing report as doubled (addr)\n");
equal_address = true;
break;
}
}
}
if (equal_stack || equal_address) {
if (!equal_stack)
ctx->racy_stacks.PushBack(hash);
if (!equal_address)
ctx->racy_addresses.PushBack(ra0);
return true;
}
return false;
}
static void AddRacyStacks(ThreadState *thr, const StackTrace (&traces)[2],
uptr addr_min, uptr addr_max) {
Context *ctx = CTX();
if (flags()->suppress_equal_stacks) {
RacyStacks hash;
hash.hash[0] = md5_hash(traces[0].Begin(), traces[0].Size() * sizeof(uptr));
hash.hash[1] = md5_hash(traces[1].Begin(), traces[1].Size() * sizeof(uptr));
ctx->racy_stacks.PushBack(hash);
}
if (flags()->suppress_equal_addresses) {
RacyAddress ra0 = {addr_min, addr_max};
ctx->racy_addresses.PushBack(ra0);
}
}
bool OutputReport(const ScopedReport &srep, const ReportStack *suppress_stack) {
const ReportDesc *rep = srep.GetReport();
bool suppressed = IsSuppressed(rep->typ, suppress_stack);
suppressed = OnReport(rep, suppressed);
if (suppressed)
return false;
PrintReport(rep);
CTX()->nreported++;
return true;
}
void ReportRace(ThreadState *thr) {
ScopedInRtl in_rtl;
uptr addr = ShadowToMem((uptr)thr->racy_shadow_addr);
uptr addr_min = 0;
uptr addr_max = 0;
{
uptr a0 = addr + Shadow(thr->racy_state[0]).addr0();
uptr a1 = addr + Shadow(thr->racy_state[1]).addr0();
uptr e0 = a0 + Shadow(thr->racy_state[0]).size();
uptr e1 = a1 + Shadow(thr->racy_state[1]).size();
addr_min = min(a0, a1);
addr_max = max(e0, e1);
if (IsExpectedReport(addr_min, addr_max - addr_min))
return;
}
Context *ctx = CTX();
Lock l0(&ctx->thread_mtx);
ScopedReport rep(ReportTypeRace);
const uptr nmop = thr->racy_state[1] == kShadowFreed ? 1 : 2;
StackTrace traces[2];
for (uptr i = 0; i < nmop; i++) {
Shadow s(thr->racy_state[i]);
RestoreStack(s.tid(), s.epoch(), &traces[i]);
}
if (HandleRacyStacks(thr, traces, addr_min, addr_max))
return;
for (uptr i = 0; i < nmop; i++) {
Shadow s(thr->racy_state[i]);
rep.AddMemoryAccess(addr, s, &traces[i]);
}
// Ensure that we have at least something for the current thread.
CHECK_EQ(traces[0].IsEmpty(), false);
for (uptr i = 0; i < nmop; i++) {
FastState s(thr->racy_state[i]);
ThreadContext *tctx = ctx->threads[s.tid()];
if (s.epoch() < tctx->epoch0 || s.epoch() > tctx->epoch1)
continue;
rep.AddThread(tctx);
}
if (!OutputReport(rep, rep.GetReport()->mops[0]->stack))
return;
AddRacyStacks(thr, traces, addr_min, addr_max);
// Bump the thread's clock a bit.
// This avoids series of similar reports between the same threads
// that happen close to each other (e.g. accessing several fields
// of the same object).
FastState s(thr->racy_state[1]);
thr->clock.set(s.tid(), s.epoch() + 100);
}
void CheckFailed(const char *file, int line, const char *cond, u64 v1, u64 v2) {
ScopedInRtl in_rtl;
Printf("FATAL: ThreadSanitizer CHECK failed: %s:%d \"%s\" (%llx, %llx)\n",
file, line, cond, v1, v2);
Die();
}
} // namespace __tsan