Merge #18162: util: Avoid potential uninitialized read in FormatISO8601DateTime(int64_t) by checking gmtime_s/gmtime_r return value

12a2f377185a413b740460db36812de22ee2e041 util: Avoid potential uninitialized read in FormatISO8601DateTime(int64_t nTime) by checking gmtime_s/gmtime_r return value (practicalswift)

Pull request description:

  Avoid potential uninitialized read in `FormatISO8601DateTime(int64_t)` by checking `gmtime_s`/`gmtime_r` return value.

  Before this patch `FormatISO8601DateTime(67768036191676800)` resulted in:

  ```
  ==5930== Conditional jump or move depends on uninitialised value(s)
  ==5930==    at 0x4F44C0A: std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_int<long>(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, long) const (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.25)
  ==5930==    by 0x4F511A4: std::ostream& std::ostream::_M_insert<long>(long) (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.25)
  ==5930==    by 0x4037C3: void tinyformat::formatValue<int>(std::ostream&, char const*, char const*, int, int const&) (tinyformat.h:358)
  ==5930==    by 0x403725: void tinyformat::detail::FormatArg::formatImpl<int>(std::ostream&, char const*, char const*, int, void const*) (tinyformat.h:543)
  ==5930==    by 0x402E02: tinyformat::detail::FormatArg::format(std::ostream&, char const*, char const*, int) const (tinyformat.h:528)
  ==5930==    by 0x401B16: tinyformat::detail::formatImpl(std::ostream&, char const*, tinyformat::detail::FormatArg const*, int) (tinyformat.h:907)
  ==5930==    by 0x4017AE: tinyformat::vformat(std::ostream&, char const*, tinyformat::FormatList const&) (tinyformat.h:1054)
  ==5930==    by 0x401765: void tinyformat::format<int, int, int, int, int, int>(std::ostream&, char const*, int const&, int const&, int const&, int const&, int const&, int const&) (tinyformat.h:1064)
  ==5930==    by 0x401656: std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > tinyformat::format<int, int, int, int, int, int>(char const*, int const&, int const&, int const&, int const&, int const&, int const&) (tinyformat.h:1073)
  ==5930==    by 0x4014CC: FormatISO8601DateTime[abi:cxx11](long) (…)
  ```

  The same goes for other very large positive and negative arguments.

  Fix by simply checking the `gmtime_s`/`gmtime_r` return value :)

ACKs for top commit:
  MarcoFalke:
    ACK 12a2f377185a413b740460db36812de22ee2e041
  theStack:
    re-ACK 12a2f37718
  elichai:
    re ACK 12a2f377185a413b740460db36812de22ee2e041

Tree-SHA512: 066142670d9bf0944d41fa3f3c702b1a460b5471b93e76a619b1e818ff9bb9c09fe14c4c37e9536a04c99533f7f21d1b08ac141e1b829ff87ee54c80d0e61d48
This commit is contained in:
fanquake 2020-02-25 09:51:13 +08:00 committed by munkybooty
parent 352744d222
commit 02aac6b0f8
2 changed files with 9 additions and 5 deletions

View File

@ -12,7 +12,7 @@ export NO_DEPENDS=1
export RUN_UNIT_TESTS=false
export RUN_FUNCTIONAL_TESTS=false
export RUN_FUZZ_TESTS=true
export FUZZ_TESTS_CONFIG="--exclude integer,parse_iso8601 --valgrind"
export FUZZ_TESTS_CONFIG="--valgrind"
export GOAL="install"
export BITCOIN_CONFIG="--enable-fuzz --with-sanitizers=fuzzer CC=clang-8 CXX=clang++-8"
# Use clang-8, instead of default clang on bionic, which is clang-6 and does not come with libfuzzer on aarch64

View File

@ -77,10 +77,12 @@ std::string FormatISO8601DateTime(int64_t nTime) {
struct tm ts;
time_t time_val = nTime;
#ifdef HAVE_GMTIME_R
gmtime_r(&time_val, &ts);
if (gmtime_r(&time_val, &ts) == nullptr) {
#else
gmtime_s(&ts, &time_val);
if (gmtime_s(&ts, &time_val) != 0) {
#endif
return {};
}
return strprintf("%04i-%02i-%02iT%02i:%02i:%02iZ", ts.tm_year + 1900, ts.tm_mon + 1, ts.tm_mday, ts.tm_hour, ts.tm_min, ts.tm_sec);
}
@ -88,10 +90,12 @@ std::string FormatISO8601Date(int64_t nTime) {
struct tm ts;
time_t time_val = nTime;
#ifdef HAVE_GMTIME_R
gmtime_r(&time_val, &ts);
if (gmtime_r(&time_val, &ts) == nullptr) {
#else
gmtime_s(&ts, &time_val);
if (gmtime_s(&ts, &time_val) != 0) {
#endif
return {};
}
return strprintf("%04i-%02i-%02i", ts.tm_year + 1900, ts.tm_mon + 1, ts.tm_mday);
}