Libfuzzer fix for Ctrl + c not working with -fork and -ignore_crashes=1

[SyrasX]

Summary

In some cases running Libfuzzer in fork mode with -ignore_crashes=1 counts ctrl+c as crash and restarts.

Thread: https://github.com/google/oss-fuzz/issues/4547

Credit: Marcel Boehme <[e-mail]>

[vitalybuka]

compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp

29

why this does not use Options->InterruptExitCode?

[SyrasX]

FuzzingOptions->InterruptExitCode

[SyrasX]

compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp

29

Yeah just inattention sorry.

[SyrasX]

Is there anything I need to do after the diff got accepted ? Don't think I have a way to commit. @vitalybuka

[vitalybuka]

I can land it for you, but can't figure out email to attach to the commit.

[SyrasX]

In D130990#3724005, @vitalybuka wrote:

I can land it for you, but can't figure out email to attach to the commit.

Thanks, should be [e-mail]

[vitalybuka]

update

compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp

 #include <unistd.h>
 
 
 namespace fuzzer {
 
 int ExecuteCommand(const Command &Cmd) {
   std::string CmdLine = Cmd.toString();
   int exit_code = system(CmdLine.c_str());
-  if (WIFEXITED(exit_code))
+  if (WIFEXITED(exit_code)){
     return WEXITSTATUS(exit_code);
+  } else if (WIFSIGNALED(exit_code) && WTERMSIG(exit_code) == SIGINT) {
+    return 72; // Options->InterruptExitCode
+  }
   return exit_code;
 }
 
 void DiscardOutput(int Fd) {
   FILE* Temp = fopen("/dev/null", "w");
   if (!Temp)
     return;
   dup2(fileno(Temp), Fd);
   fclose(Temp);
 }
 
 } // namespace fuzzer
 
 #endif