Hi Everyone, We are catching an uninitialized read finding using Valgrind Git Master. The head of the finding is shown below.
I suspect it is a valid finding but it kind of strikes me as odd that x86_64 without any -march or -m options is using SSE4. In fact, we build without -march and -m options because that's how distros want it. It feels like I should work on the capabilities problem first rather than chasing the uninitialized read. I can envision a situation where some component assumes a higher ISA is available so it performs an operation on a data structure that should not happen. My question is, where should I begin to look for the root cause? Is this STL or libstdc++? Or maybe glibc? ********** Here's how all files are compiled. $ make valgrind -j 10 g++ -DNDEBUG -g3 -O1 -fPIC -pthread -pipe -DCRYPTOPP_VALGRIND -c cryptlib.cpp g++ -DNDEBUG -g3 -O1 -fPIC -pthread -pipe -DCRYPTOPP_VALGRIND -c cpu.cpp g++ -DNDEBUG -g3 -O1 -fPIC -pthread -pipe -DCRYPTOPP_VALGRIND -c integer.cpp ... ********** Testing SymmetricCipher algorithm Salsa20. ......==2518== Conditional jump or move depends on uninitialised value(s) ==2518== at 0x4C34C26: __memcmp_sse4_1 (vg_replace_strmem.c:1099) ==2518== by 0x48B435: compare (char_traits.h:310) ==2518== by 0x48B435: __gnu_cxx::__enable_if<std::__is_char<char>::__value, bool>::__type std::operator==<char>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) (basic_string.h:6006) ==2518== by 0x4F8BAD: operator!=<char, std::char_traits<char>, std::allocator<char> > (basic_string.h:6045) ==2518== by 0x4F8BAD: CryptoPP::Test::TestSymmetricCipher(std::map<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >&, CryptoPP::NameValuePairs const&) (datatest.cpp:514) ... ********** And here is the data test that is failing. Its a torture test, and the "r131072" say "create a string that is 128KB of all 0's": Key: 0F62B5085BAE0154A7FA4DA0F34699EC3F92E5388BDE3184D72A7DD02376C91C IV: 288FF65DC42B92F9 Plaintext: r131072 00 CiphertextXorDigest: E00EBCCD70D69152725F9987982178A2 ... (32 byte omitted) Test: EncryptXorDigest ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Valgrind-users mailing list Valgrind-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/valgrind-users
