From 1301552101af899557a93a7535d8a57874fe6edf Mon Sep 17 00:00:00 2001 From: Dominik Maier Date: Sun, 23 Aug 2020 01:48:36 +0200 Subject: added AFL_MAX_DET_EXTRAS env var --- src/afl-fuzz-state.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'src/afl-fuzz-state.c') diff --git a/src/afl-fuzz-state.c b/src/afl-fuzz-state.c index dd0e316c..74798584 100644 --- a/src/afl-fuzz-state.c +++ b/src/afl-fuzz-state.c @@ -349,6 +349,13 @@ void read_afl_environment(afl_state_t *afl, char **envp) { afl->afl_env.afl_preload = (u8 *)get_afl_env(afl_environment_variables[i]); + } else if (!strncmp(env, "AFL_MAX_DET_EXTRAS", + + afl_environment_variable_len)) { + + afl->afl_env.afl_max_det_extras = + (u8 *)get_afl_env(afl_environment_variables[i]); + } } else { -- cgit 1.4.1 From 425908a00cdcaa4d49a513d283431b8b6eed0486 Mon Sep 17 00:00:00 2001 From: Marius Muench Date: Sun, 23 Aug 2020 10:39:34 +0200 Subject: 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. --- .gitignore | 1 + include/afl-fuzz.h | 3 ++- include/envs.h | 1 + include/forkserver.h | 1 + src/afl-forkserver.c | 6 ++++-- src/afl-fuzz-state.c | 7 +++++++ src/afl-fuzz.c | 17 +++++++++++++++++ 7 files changed, 33 insertions(+), 3 deletions(-) (limited to 'src/afl-fuzz-state.c') diff --git a/.gitignore b/.gitignore index b2c2fc62..4307fc4c 100644 --- a/.gitignore +++ b/.gitignore @@ -3,6 +3,7 @@ .sync_tmp *.o *.so +*.swp *.pyc *.dSYM as diff --git a/include/afl-fuzz.h b/include/afl-fuzz.h index 148e6e84..1f1dda3a 100644 --- a/include/afl-fuzz.h +++ b/include/afl-fuzz.h @@ -353,7 +353,8 @@ typedef struct afl_env_vars { afl_cal_fast, afl_cycle_schedules, afl_expand_havoc; u8 *afl_tmpdir, *afl_custom_mutator_library, *afl_python_module, *afl_path, - *afl_hang_tmout, *afl_skip_crashes, *afl_preload, *afl_max_det_extras; + *afl_hang_tmout, *afl_forksrv_init_tmout, *afl_skip_crashes, *afl_preload, + *afl_max_det_extras; } afl_env_vars_t; 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", diff --git a/include/forkserver.h b/include/forkserver.h index d824c1c9..300ecffc 100644 --- a/include/forkserver.h +++ b/include/forkserver.h @@ -56,6 +56,7 @@ typedef struct afl_forkserver { u8 no_unlink; /* do not unlink cur_input */ u32 exec_tmout; /* Configurable exec timeout (ms) */ + u32 init_tmout; /* Configurable init timeout (ms) */ u32 map_size; /* map size used by the target */ u32 snapshot; /* is snapshot feature used */ u64 mem_limit; /* Memory cap for child (MB) */ diff --git a/src/afl-forkserver.c b/src/afl-forkserver.c index 9d9e81cd..51734579 100644 --- a/src/afl-forkserver.c +++ b/src/afl-forkserver.c @@ -79,6 +79,7 @@ void afl_fsrv_init(afl_forkserver_t *fsrv) { fsrv->use_stdin = 1; fsrv->no_unlink = 0; fsrv->exec_tmout = EXEC_TIMEOUT; + fsrv->init_tmout = EXEC_TIMEOUT * FORK_WAIT_MULT; fsrv->mem_limit = MEM_LIMIT; fsrv->out_file = NULL; @@ -101,6 +102,7 @@ void afl_fsrv_init_dup(afl_forkserver_t *fsrv_to, afl_forkserver_t *from) { fsrv_to->out_fd = from->out_fd; fsrv_to->dev_null_fd = from->dev_null_fd; fsrv_to->exec_tmout = from->exec_tmout; + fsrv_to->init_tmout = from->init_tmout; fsrv_to->mem_limit = from->mem_limit; fsrv_to->map_size = from->map_size; fsrv_to->support_shmem_fuzz = from->support_shmem_fuzz; @@ -519,13 +521,13 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, u32 time_ms = read_s32_timed(fsrv->fsrv_st_fd, &status, - fsrv->exec_tmout * FORK_WAIT_MULT, stop_soon_p); + fsrv->init_tmout, stop_soon_p); if (!time_ms) { kill(fsrv->fsrv_pid, SIGKILL); - } else if (time_ms > fsrv->exec_tmout * FORK_WAIT_MULT) { + } else if (time_ms > fsrv->init_tmout) { fsrv->last_run_timed_out = 1; kill(fsrv->fsrv_pid, SIGKILL); diff --git a/src/afl-fuzz-state.c b/src/afl-fuzz-state.c index 74798584..a8db8578 100644 --- a/src/afl-fuzz-state.c +++ b/src/afl-fuzz-state.c @@ -356,6 +356,13 @@ void read_afl_environment(afl_state_t *afl, char **envp) { afl->afl_env.afl_max_det_extras = (u8 *)get_afl_env(afl_environment_variables[i]); + } else if (!strncmp(env, "AFL_FORKSRV_INIT_TMOUT", + + afl_environment_variable_len)) { + + afl->afl_env.afl_forksrv_init_tmout = + (u8 *) get_afl_env(afl_environment_variables[i]); + } } else { diff --git a/src/afl-fuzz.c b/src/afl-fuzz.c index 664cc076..ae5cb087 100644 --- a/src/afl-fuzz.c +++ b/src/afl-fuzz.c @@ -173,6 +173,7 @@ static void usage(u8 *argv0, int more_help) { "AFL_FAST_CAL: limit the calibration stage to three cycles for speedup\n" "AFL_FORCE_UI: force showing the status screen (for virtual consoles)\n" "AFL_HANG_TMOUT: override timeout value (in milliseconds)\n" + "AFL_FORKSRV_INIT_TMOUT: time spent waiting for forkserver during startup (in milliseconds)\n" "AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES: don't warn about core dump handlers\n" "AFL_IMPORT_FIRST: sync and import test cases from other fuzzer instances first\n" "AFL_MAP_SIZE: the shared memory size for that target. must be >= the size\n" @@ -969,6 +970,22 @@ int main(int argc, char **argv_orig, char **envp) { } + if (afl->afl_env.afl_forksrv_init_tmout) { + + afl->fsrv.init_tmout = atoi(afl->afl_env.afl_forksrv_init_tmout); + if (!afl->fsrv.init_tmout) { + + FATAL("Invalid value of AFL_FORKSRV_INIT_TMOUT"); + + } + + } else { + + afl->fsrv.init_tmout = afl->fsrv.exec_tmout * FORK_WAIT_MULT; + + } + + if (afl->non_instrumented_mode == 2 && afl->no_forkserver) { FATAL("AFL_DUMB_FORKSRV and AFL_NO_FORKSRV are mutually exclusive"); -- cgit 1.4.1 From e2b54bfa0540d074423260bec01a544e9beda1df Mon Sep 17 00:00:00 2001 From: Dominik Maier Date: Sun, 23 Aug 2020 10:40:46 +0200 Subject: code format --- src/afl-forkserver.c | 5 ++--- src/afl-fuzz-state.c | 2 +- src/afl-fuzz.c | 1 - 3 files changed, 3 insertions(+), 5 deletions(-) (limited to 'src/afl-fuzz-state.c') diff --git a/src/afl-forkserver.c b/src/afl-forkserver.c index 51734579..c496975f 100644 --- a/src/afl-forkserver.c +++ b/src/afl-forkserver.c @@ -519,9 +519,8 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, rlen = 0; if (fsrv->exec_tmout) { - u32 time_ms = - read_s32_timed(fsrv->fsrv_st_fd, &status, - fsrv->init_tmout, stop_soon_p); + u32 time_ms = read_s32_timed(fsrv->fsrv_st_fd, &status, fsrv->init_tmout, + stop_soon_p); if (!time_ms) { diff --git a/src/afl-fuzz-state.c b/src/afl-fuzz-state.c index a8db8578..577fc34f 100644 --- a/src/afl-fuzz-state.c +++ b/src/afl-fuzz-state.c @@ -361,7 +361,7 @@ void read_afl_environment(afl_state_t *afl, char **envp) { afl_environment_variable_len)) { afl->afl_env.afl_forksrv_init_tmout = - (u8 *) get_afl_env(afl_environment_variables[i]); + (u8 *)get_afl_env(afl_environment_variables[i]); } diff --git a/src/afl-fuzz.c b/src/afl-fuzz.c index ae5cb087..1abd49d8 100644 --- a/src/afl-fuzz.c +++ b/src/afl-fuzz.c @@ -985,7 +985,6 @@ int main(int argc, char **argv_orig, char **envp) { } - if (afl->non_instrumented_mode == 2 && afl->no_forkserver) { FATAL("AFL_DUMB_FORKSRV and AFL_NO_FORKSRV are mutually exclusive"); -- cgit 1.4.1