refs #341 - added fuzzing client

[firewave]

[firewave]

Will be made ready to review after #339 has been merged.

[firewave]

Since we do not have a OSS-Fuzz integration yet we should at least do a simple run in the CI (a run-time of 60 seconds should be fine). This can be enhanced by providing a corpus (see #608).

[firewave]

Something is wrong with the fuzzer in the CI. It generates much less data.

Using the testrunner corpus it shows:

INFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 2331061488
INFO: Loaded 1 modules   (129 inline 8-bit counters): 129 [0x55e1d44a8490, 0x55e1d44a8511), 
INFO: Loaded 1 PC tables (129 PCs): 129 [0x55e1d44a8518,0x55e1d44a8d28), 
INFO: -fork=4: fuzzing in separate process(s)
INFO: -fork=4: 53 seed inputs, starting to fuzz in /tmp/libFuzzerTemp.FuzzWithFork4741.dir
#8850: cov: 197 ft: 197 corp: 53 exec/s: 4425 oom/timeout/crash: 0/0/0 time: 2s job: 1 dft_time: 0

When I use the same corpus locally I get

NFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 629331751
INFO: Loaded 1 modules   (8638 inline 8-bit counters): 8638 [0x55dc70ee0c70, 0x55dc70ee2e2e), 
INFO: Loaded 1 PC tables (8638 PCs): 8638 [0x55dc70ee2e30,0x55dc70f04a10), 
INFO: -fork=4: fuzzing in separate process(s)
INFO: -fork=4: 298 seed inputs, starting to fuzz in /tmp/libFuzzerTemp.FuzzWithFork335544.dir
#6327: cov: 2375 ft: 5411 corp: 298 exec/s: 3163 oom/timeout/crash: 0/0/0 time: 2s job: 1 dft_time: 0

[firewave]

Something is wrong with the fuzzer in the CI. It generates much less data.

I forgot to clean the existing files so it was using non-instrumented code.