https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63297
Bug ID: 63297 Summary: ASan reported heap-use-after-free in g++.old-deja/g++.law/virtual3.C. Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: testsuite Assignee: unassigned at gcc dot gnu.org Reporter: chefmax at gcc dot gnu.org Host: x86_64-pc-linux-gnu Target: x86_64-pc-linux-gnu Created attachment 33512 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33512&action=edit This trivial patch seems to fix the issue. ASan reported heap-use-after-free in g++.old-deja/g++.law/virtual3.C: $ ~/install/master/bin/g++ gcc/testsuite/g++.old-deja/g++.law/virtual3.C -fsanitize=address $ ./a.out ================================================================= ==26271==ERROR: AddressSanitizer: heap-use-after-free on address 0x60300000eff8 at pc 0x7fd84fbb6470 bp 0x7fff4d8204a0 sp 0x7fff4d81fc60 READ of size 5 at 0x60300000eff8 thread T0 #0 0x7fd84fbb646f in __interceptor_strlen /home/max/workspace/downloads/gcc/libsanitizer/asan/asan_interceptors.cc:536 #1 0x7fd84f8ed2d8 in std::char_traits<char>::length(char const*) /home/max/build/master-x86_64/x86_64-unknown-linux-gnu/libstdc++-v3/include/bits/char_traits.h:263 #2 0x7fd84f8ed2d8 in std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*) /home/max/build/master-x86_64/x86_64-unknown-linux-gnu/libstdc++-v3/include/ostream:536 #3 0x401515 in BugStream::eval() (/home/max/workspace/downloads/gcc/a.out+0x401515) #4 0x4015ef in operator<<(std::ostream&, Eval_) (/home/max/workspace/downloads/gcc/a.out+0x4015ef) #5 0x401699 in main (/home/max/workspace/downloads/gcc/a.out+0x401699) #6 0x7fd84efa576c in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2176c) #7 0x4013c8 (/home/max/workspace/downloads/gcc/a.out+0x4013c8) 0x60300000eff8 is located 24 bytes inside of 30-byte region [0x60300000efe0,0x60300000effe) freed by thread T0 here: #0 0x7fd84fbf36a9 in operator delete(void*) /home/max/workspace/downloads/gcc/libsanitizer/asan/asan_new_delete.cc:85 #1 0x7fd84f914eef in std::string::_Rep::_M_dispose(std::allocator<char> const&) /home/max/build/master-x86_64/x86_64-unknown-linux-gnu/libstdc++-v3/include/bits/basic_string.h:249 #2 0x7fd84f914eef in std::basic_string<char, std::char_traits<char>, std::allocator<char> >::~basic_string() /home/max/build/master-x86_64/x86_64-unknown-linux-gnu/libstdc++-v3/include/bits/basic_string.h:547 #3 0x4015ef in operator<<(std::ostream&, Eval_) (/home/max/workspace/downloads/gcc/a.out+0x4015ef) #4 0x401699 in main (/home/max/workspace/downloads/gcc/a.out+0x401699) #5 0x7fd84efa576c in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2176c) previously allocated by thread T0 here: #0 0x7fd84fbf3169 in operator new(unsigned long) /home/max/workspace/downloads/gcc/libsanitizer/asan/asan_new_delete.cc:53 #1 0x7fd84f914d18 in __gnu_cxx::new_allocator<char>::allocate(unsigned long, void const*) /home/max/build/master-x86_64/x86_64-unknown-linux-gnu/libstdc++-v3/include/ext/new_allocator.h:104 #2 0x7fd84f914d18 in std::string::_Rep::_S_create(unsigned long, unsigned long, std::allocator<char> const&) /home/max/build/master-x86_64/x86_64-unknown-linux-gnu/libstdc++-v3/include/bits/basic_string.tcc:607 SUMMARY: AddressSanitizer: heap-use-after-free /home/max/workspace/downloads/gcc/libsanitizer/asan/asan_interceptors.cc:536 __interceptor_strlen Shadow bytes around the buggy address: 0x0c067fff9da0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9db0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9dc0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9dd0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9de0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa =>0x0c067fff9df0: fa fa fa fa fa fa fa fa fa fa fa fa fd fd fd[fd] 0x0c067fff9e00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9e10: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9e20: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9e30: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c067fff9e40: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc ASan internal: fe ==26271==ABORTING