llvm-project

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//===-- ubsan_monitor.cpp ---------------------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// Hooks which allow a monitor process to inspect UBSan's diagnostics.
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//
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//===----------------------------------------------------------------------===//
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#include "ubsan_monitor.h"
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using namespace __ubsan;
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UndefinedBehaviorReport::UndefinedBehaviorReport(const char *IssueKind,
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                                                 Location &Loc,
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                                                 InternalScopedString &Msg)
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    : IssueKind(IssueKind), Loc(Loc) {
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  // We have the common sanitizer reporting lock, so it's safe to register a
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  // new UB report.
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  RegisterUndefinedBehaviorReport(this);
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  // Make a copy of the diagnostic.
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  if (Msg.length())
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    Buffer.Append(Msg.data());
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  // Let the monitor know that a report is available.
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  __ubsan_on_report();
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}
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static UndefinedBehaviorReport *CurrentUBR;
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void __ubsan::RegisterUndefinedBehaviorReport(UndefinedBehaviorReport *UBR) {
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  CurrentUBR = UBR;
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}
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SANITIZER_WEAK_DEFAULT_IMPL
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void __ubsan::__ubsan_on_report(void) {}
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void __ubsan::__ubsan_get_current_report_data(const char **OutIssueKind,
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                                              const char **OutMessage,
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                                              const char **OutFilename,
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                                              unsigned *OutLine,
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                                              unsigned *OutCol,
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                                              char **OutMemoryAddr) {
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  if (!OutIssueKind || !OutMessage || !OutFilename || !OutLine || !OutCol ||
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      !OutMemoryAddr)
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    UNREACHABLE("Invalid arguments passed to __ubsan_get_current_report_data");
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  InternalScopedString &Buf = CurrentUBR->Buffer;
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  // Ensure that the first character of the diagnostic text can't start with a
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  // lowercase letter.
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  char FirstChar = *Buf.data();
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  if (FirstChar >= 'a' && FirstChar <= 'z')
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    *Buf.data() += 'A' - 'a';
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  *OutIssueKind = CurrentUBR->IssueKind;
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  *OutMessage = Buf.data();
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  if (!CurrentUBR->Loc.isSourceLocation()) {
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    *OutFilename = "<unknown>";
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    *OutLine = *OutCol = 0;
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  } else {
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    SourceLocation SL = CurrentUBR->Loc.getSourceLocation();
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    *OutFilename = SL.getFilename();
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    *OutLine = SL.getLine();
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    *OutCol = SL.getColumn();
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  }
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  if (CurrentUBR->Loc.isMemoryLocation())
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    *OutMemoryAddr = (char *)CurrentUBR->Loc.getMemoryLocation();
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  else
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    *OutMemoryAddr = nullptr;
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}
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