OSS-fuzz build is failing because 'cargo fuzz' fails to build

[BurntSushi]

Here's the OSS-fuzz ticket: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32817

Here's the build log: https://oss-fuzz-build-logs.storage.googleapis.com/log-c25752c4-6e8b-4e9c-b09d-0a488f5bb1a9.txt

The relevant section is:

Starting Step #3
Step #3: Already have image: gcr.io/oss-fuzz/rust-regex
Step #3: ---------------------------------------------------------------
Step #3: Compiling libFuzzer to /usr/lib/libFuzzingEngine.a...  done.
Step #3: ---------------------------------------------------------------
Step #3: CC=clang
Step #3: CXX=clang++
Step #3: CFLAGS=-O1 -fno-omit-frame-pointer -gline-tables-only -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION  -fprofile-instr-generate -fcoverage-mapping -pthread -Wl,--no-as-needed -Wl,-ldl -Wl,-lm -Wno-unused-command-line-argument
Step #3: CXXFLAGS=-O1 -fno-omit-frame-pointer -gline-tables-only -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION  -fprofile-instr-generate -fcoverage-mapping -pthread -Wl,--no-as-needed -Wl,-ldl -Wl,-lm -Wno-unused-command-line-argument -stdlib=libc++
Step #3: ---------------------------------------------------------------
Step #3: + cd /src/regex
Step #3: + cargo fuzz build -O
Step #3: warning: /src/regex/fuzz/Cargo.toml: use `[profile.dev]` to configure debug builds
Step #3:     Updating crates.io index
Step #3:  Downloading crates ...
Step #3:   Downloaded arbitrary v0.4.7
Step #3:   Downloaded memchr v2.3.4
Step #3:   Downloaded cc v1.0.67
Step #3:   Downloaded libfuzzer-sys v0.3.5
Step #3:   Downloaded aho-corasick v0.7.15
Step #3:    Compiling memchr v2.3.4
Step #3:    Compiling cc v1.0.67
Step #3:    Compiling regex-syntax v0.6.23 (/src/regex/regex-syntax)
Step #3:    Compiling arbitrary v0.4.7
Step #3:    Compiling aho-corasick v0.7.15
Step #3:    Compiling libfuzzer-sys v0.3.5
Step #3: error: symbol `_RINvMNtNtCskrsM4FCwAVA_4core3ptr7mut_ptrOINtNtCs2beRm3ZGvIF_5alloc3vec3VecINtNtBI_5boxed3BoxDNtNtNtNtB7_4iter6traits8iterator8Iteratorp4ItemcEL_EE4castuECs9KydpJjV7w1_9arbitrary` is already defined
Step #3: 
Step #3: error: aborting due to previous error
Step #3: 
Step #3: error: could not compile `arbitrary`
Step #3: 
Step #3: To learn more, run the command again with --verbose.
Step #3: warning: build failed, waiting for other jobs to finish...
Step #3: error: build failed

But when I run cargo fuzz build -O locally, it completes successfully. It would be much appreciated if someone who knows more about OSS-fuzz could help here. I did try to run the Docker image the build appears to be using directly, but it couldn't be found:

$ docker run -it --rm gcr.io/oss-fuzz/rust-regex:latest bash
Unable to find image 'gcr.io/oss-fuzz/rust-regex:latest' locally
docker: Error response from daemon: manifest for gcr.io/oss-fuzz/rust-regex:latest not found: manifest unknown: Failed to fetch "latest" from request "/v2/oss-fuzz/rust-regex/manifests/latest".

cc @DavidKorczynski

[DavidKorczynski]

I think this is because we need to update libfuzzer-sys v0.3.5 to libfuzzer-sys v0.4.0 - give me a few moments to verify

[BurntSushi]

Interesting. When I ran cargo fuzz locally, it does seem to be using 0.3.5 though and it works:

$ cargo fuzz build -O
warning: /home/andrew/rust/regex/fuzz/Cargo.toml: use `[profile.dev]` to configure debug builds
    Updating crates.io index
  Downloaded cc v1.0.67
  Downloaded arbitrary v0.4.7
  Downloaded libfuzzer-sys v0.3.5
  Downloaded 3 crates (192.2 KB) in 0.19s
   Compiling memchr v2.3.4
   Compiling cc v1.0.67
   Compiling arbitrary v0.4.7
   Compiling regex-syntax v0.6.23 (/home/andrew/rust/regex/regex-syntax)
   Compiling aho-corasick v0.7.15
   Compiling libfuzzer-sys v0.3.5
   Compiling regex v1.4.5 (/home/andrew/rust/regex)
   Compiling regex-fuzz v0.0.0 (/home/andrew/rust/regex/fuzz)
    Finished release [optimized + debuginfo] target(s) in 40.02s

But maybe there is some other environment issue that I'm missing. In any case, thank you very much for looking into this!

[DavidKorczynski]

Notice that it is only the coverage build (i.e. python infra/helper.py build_fuzzers --sanitizer=coverage rust-regex) that fails. The other sanitizers work.

I just tested locally and confirm it works with version 0.4.0. Pushed a fix here: #758