https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85660
Bug ID: 85660 Summary: Signed Integer Overflow (79257474) Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: demangler Assignee: unassigned at gcc dot gnu.org Reporter: security-tps at google dot com Target Milestone: --- Created attachment 44075 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44075&action=edit proof of concept Hello, As part of our fuzzing efforts at Google, we have identified an issue affecting binutils (tested with revision * master 4e6fe7477a4e9260777cbaa01f70df7ae5f063bb). To reproduce, we are attaching a Dockerfile which compiles the project with LLVM, taking advantage of the sanitizers that it offers. More information about how to use the attached Dockerfile can be found here: https://docs.docker.com/engine/reference/builder/ Instructions: `unzip artifacts_79257474.zip` `docker build --build-arg SANITIZER=undefined --tag=autofuzz-binutils-79257474 autofuzz_79257474` `docker run --entrypoint /fuzzing/repro.sh --cap-add=SYS_PTRACE -v $PWD/autofuzz_79257474/poc-7c8bacd8e3b958d37b7a4c80eb649af20e1eae6828f838d518a18781c03c438a_min:/tmp/poc autofuzz-binutils-79257474 "" /tmp/poc` `docker run --cap-add=SYS_PTRACE -v $PWD/autofuzz_79257474/poc-7c8bacd8e3b958d37b7a4c80eb649af20e1eae6828f838d518a18781c03c438a_min:/tmp/poc -it autofuzz-binutils-79257474` Alternatively, and depending on the bug, you could use gcc, valgrind or other instrumentation tools to aid in the investigation. The sanitizer error that we encountered is here: ``` INFO: Seed: 1481494163 INFO: Loaded 0 modules (0 guards): /fuzzing/binutils-gdb/build/demangle_fuzzer: Running 1 inputs 500 time(s) each. Running: /tmp/poc-7c8bacd8e3b958d37b7a4c80eb649af20e1eae6828f838d518a18781c03c438a /fuzzing/binutils-gdb/libiberty/cplus-dem.c:3597:10: runtime error: signed integer overflow: 666666616 * 10 cannot be represented in type 'int' #0 0x4332c3 in get_count /fuzzing/binutils-gdb/libiberty/cplus-dem.c:3597:10 #1 0x42d0bd in do_type /fuzzing/binutils-gdb/libiberty/cplus-dem.c:3874:12 #2 0x4319f4 in demangle_template /fuzzing/binutils-gdb/libiberty/cplus-dem.c:2300:14 #3 0x43027a in demangle_signature /fuzzing/binutils-gdb/libiberty/cplus-dem.c:1628:14 #4 0x42e864 in internal_cplus_demangle /fuzzing/binutils-gdb/libiberty/cplus-dem.c:1257:14 #5 0x42d990 in cplus_demangle /fuzzing/binutils-gdb/libiberty/cplus-dem.c:918:9 #6 0x42bf02 in LLVMFuzzerTestOneInput /fuzzing/security-research-pocs/autofuzz/demangle_fuzzer.cc:11:21 #7 0x4557ee in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) (/fuzzing/binutils-gdb/build/demangle_fuzzer+0x4557ee) #8 0x44a93e in fuzzer::RunOneTest(fuzzer::Fuzzer*, char const*, unsigned long) (/fuzzing/binutils-gdb/build/demangle_fuzzer+0x44a93e) #9 0x44ee47 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) (/fuzzing/binutils-gdb/build/demangle_fuzzer+0x44ee47) #10 0x44a65b in main (/fuzzing/binutils-gdb/build/demangle_fuzzer+0x44a65b) #11 0x7f090766c2e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0) #12 0x406a69 in _start (/fuzzing/binutils-gdb/build/demangle_fuzzer+0x406a69) SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /fuzzing/binutils-gdb/libiberty/cplus-dem.c:3597:10 in ``` We will gladly work with you so you can successfully confirm and reproduce this issue. Do let us know if you have any feedback surrounding the documentation. Once you have reproduced the issue, we'd appreciate to learn your expected timeline for an update to be released. With any fix, please attribute the report to "Google Autofuzz project". We are also pleased to inform you that your project is eligible for inclusion to the OSS-Fuzz project, which can provide additional continuous fuzzing, and encourage you to investigate integration options. Don't hesitate to let us know if you have any questions! Google AutoFuzz Team