googleprojectzero
WinAfl internal crash during the running
I ran 4 instances of the fuzzer. They worked well but three of them crashed after a few hours
SYSTEM ERROR : Unable to create "path\fuzzer03.cur_input" stop location: write_to_testcase(), c:\work\winafl\source\afl-fuzz.c:2689 Os message : file exsist
Why is this happening suddenly and how to solve it?
This is possibly related to https://github.com/googleprojectzero/winafl/issues/97 where it was suggested that using a different DynamoRIO version helps. What happens in the other bug is, occasionally DR process ends in a state where it can't be killed, but still holds a reference to the input file, and so the input file can't be rewritten for the next iteration. However, in that case, afl-fuzz should throw an error when attempting to kill the DR process and the error message you're seeing is different, so I'm not 100% sure it's the same thing. If not, then I'm not sure what might be causing it. Perhaps something target-specific? Also worth double-checking that all your fuzzer instances have different IDs.
