Option for specifying forkserver initialization timeout via environment variable (#522)

* Addition of AFL_FORKSRV_INIT_TMOUT env var

This commit introduces a new environment variable which allows to
specify the timespan AFL should wait for initial contact with the
forkserver.

This is useful for fuzz-targets requiring a rather long setup time
before the actual fuzzing can be started (e.g., unicorn).

* add .swp files to .gitignore

* Inherit init_tmout in afl_fsrv_init_dup

Without this patch, the forkserver would spawn with a timeout of 0 in
cmplog mode, leading to an immediate crash.

Additionally, this commit removes a spurious whitespace.

* Initialize afl->fsrv.init_tmout in afl_fsrv_init

Not all afl-components will need the new AFL_FORKSRV_INIT_TMOUT
environment variable. Hence, it's initialized to the safe "default"
value from before in afl_fsrv_init now.

1 files changed, 1 insertions, 0 deletions

diff --git a/include/envs.h b/include/envs.h
index 4d50d0ff..c7761e19 100644
--- a/include/envs.h
+++ b/include/envs.h
@@ -48,6 +48,7 @@ static char *afl_environment_variables[] = {
     "AFL_GCC_INSTRUMENT_FILE",
     "AFL_GCJ",
     "AFL_HANG_TMOUT",
+    "AFL_FORKSRV_INIT_TMOUT",
     "AFL_HARDEN",
     "AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES",
     "AFL_IMPORT_FIRST",