diff options
Diffstat (limited to 'src/afl-forkserver.c')
| -rw-r--r-- | src/afl-forkserver.c | 79 |
1 files changed, 50 insertions, 29 deletions
diff --git a/src/afl-forkserver.c b/src/afl-forkserver.c index 90fa55e9..39f044f2 100644 --- a/src/afl-forkserver.c +++ b/src/afl-forkserver.c @@ -84,6 +84,7 @@ void afl_fsrv_init(afl_forkserver_t *fsrv) { fsrv->init_tmout = EXEC_TIMEOUT * FORK_WAIT_MULT; fsrv->mem_limit = MEM_LIMIT; fsrv->out_file = NULL; + fsrv->kill_signal = SIGKILL; /* exec related stuff */ fsrv->child_pid = -1; @@ -95,7 +96,6 @@ void afl_fsrv_init(afl_forkserver_t *fsrv) { fsrv->uses_asan = false; fsrv->init_child_func = fsrv_exec_child; - list_append(&fsrv_list, fsrv); } @@ -116,6 +116,7 @@ void afl_fsrv_init_dup(afl_forkserver_t *fsrv_to, afl_forkserver_t *from) { fsrv_to->no_unlink = from->no_unlink; fsrv_to->uses_crash_exitcode = from->uses_crash_exitcode; fsrv_to->crash_exitcode = from->crash_exitcode; + fsrv_to->kill_signal = from->kill_signal; // These are forkserver specific. fsrv_to->out_dir_fd = -1; @@ -213,7 +214,7 @@ restart_select: static void afl_fauxsrv_execv(afl_forkserver_t *fsrv, char **argv) { unsigned char tmp[4] = {0, 0, 0, 0}; - pid_t child_pid = -1; + pid_t child_pid; if (!be_quiet) { ACTF("Using Fauxserver:"); } @@ -559,12 +560,12 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, if (!time_ms) { - kill(fsrv->fsrv_pid, SIGKILL); + kill(fsrv->fsrv_pid, fsrv->kill_signal); } else if (time_ms > fsrv->init_tmout) { fsrv->last_run_timed_out = 1; - kill(fsrv->fsrv_pid, SIGKILL); + kill(fsrv->fsrv_pid, fsrv->kill_signal); } else { @@ -807,6 +808,12 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, "before receiving any input\n" " from the fuzzer! There are several probable explanations:\n\n" + " - The target binary requires a large map and crashes before " + "reporting.\n" + " Set a high value (e.g. AFL_MAP_SIZE=1024000) or use " + "AFL_DEBUG=1 to see the\n" + " message from the target binary\n\n" + " - The binary is just buggy and explodes entirely on its own. " "If so, you\n" " need to fix the underlying problem or find a better " @@ -828,6 +835,12 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, "before receiving any input\n" " from the fuzzer! There are several probable explanations:\n\n" + " - The target binary requires a large map and crashes before " + "reporting.\n" + " Set a high value (e.g. AFL_MAP_SIZE=1024000) or use " + "AFL_DEBUG=1 to see the\n" + " message from the target binary\n\n" + " - The current memory limit (%s) is too restrictive, causing " "the\n" " target to hit an OOM condition in the dynamic linker. Try " @@ -944,10 +957,10 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, static void afl_fsrv_kill(afl_forkserver_t *fsrv) { - if (fsrv->child_pid > 0) { kill(fsrv->child_pid, SIGKILL); } + if (fsrv->child_pid > 0) { kill(fsrv->child_pid, fsrv->kill_signal); } if (fsrv->fsrv_pid > 0) { - kill(fsrv->fsrv_pid, SIGKILL); + kill(fsrv->fsrv_pid, fsrv->kill_signal); if (waitpid(fsrv->fsrv_pid, NULL, 0) <= 0) { WARNF("error waitpid\n"); } } @@ -971,10 +984,10 @@ void afl_fsrv_write_to_testcase(afl_forkserver_t *fsrv, u8 *buf, size_t len) { hash64(fsrv->shmem_fuzz, *fsrv->shmem_fuzz_len, 0xa5b35705), *fsrv->shmem_fuzz_len); fprintf(stderr, "SHM :"); - for (int i = 0; i < *fsrv->shmem_fuzz_len; i++) + for (u32 i = 0; i < *fsrv->shmem_fuzz_len; i++) fprintf(stderr, "%02x", fsrv->shmem_fuzz[i]); fprintf(stderr, "\nORIG:"); - for (int i = 0; i < *fsrv->shmem_fuzz_len; i++) + for (u32 i = 0; i < *fsrv->shmem_fuzz_len; i++) fprintf(stderr, "%02x", buf[i]); fprintf(stderr, "\n"); @@ -1091,7 +1104,7 @@ fsrv_run_result_t afl_fsrv_run_target(afl_forkserver_t *fsrv, u32 timeout, /* If there was no response from forkserver after timeout seconds, we kill the child. The forkserver should inform us afterwards */ - kill(fsrv->child_pid, SIGKILL); + kill(fsrv->child_pid, fsrv->kill_signal); fsrv->last_run_timed_out = 1; if (read(fsrv->fsrv_st_fd, &fsrv->child_status, 4) < 4) { exec_ms = 0; } @@ -1104,7 +1117,7 @@ fsrv_run_result_t afl_fsrv_run_target(afl_forkserver_t *fsrv, u32 timeout, "Unable to communicate with fork server. Some possible reasons:\n\n" " - You've run out of memory. Use -m to increase the the memory " "limit\n" - " to something higher than %lld.\n" + " to something higher than %llu.\n" " - The binary or one of the libraries it uses manages to " "create\n" " threads before the forkserver initializes.\n" @@ -1137,36 +1150,44 @@ fsrv_run_result_t afl_fsrv_run_target(afl_forkserver_t *fsrv, u32 timeout, /* Report outcome to caller. */ - if (WIFSIGNALED(fsrv->child_status) && !*stop_soon_p) { + /* Was the run unsuccessful? */ + if (unlikely(*(u32 *)fsrv->trace_bits == EXEC_FAIL_SIG)) { - fsrv->last_kill_signal = WTERMSIG(fsrv->child_status); + return FSRV_RUN_ERROR; - if (fsrv->last_run_timed_out && fsrv->last_kill_signal == SIGKILL) { - - return FSRV_RUN_TMOUT; + } - } + /* Did we timeout? */ + if (unlikely(fsrv->last_run_timed_out)) { - return FSRV_RUN_CRASH; + fsrv->last_kill_signal = fsrv->kill_signal; + return FSRV_RUN_TMOUT; } - /* MSAN in uses_asan mode uses a special exit code as it doesn't support - abort_on_error. - On top, a user may specify a custom AFL_CRASH_EXITCODE. Handle both here. */ - - if ((fsrv->uses_asan && WEXITSTATUS(fsrv->child_status) == MSAN_ERROR) || - (fsrv->uses_crash_exitcode && - WEXITSTATUS(fsrv->child_status) == fsrv->crash_exitcode)) { - - fsrv->last_kill_signal = 0; + /* Did we crash? + In a normal case, (abort) WIFSIGNALED(child_status) will be set. + MSAN in uses_asan mode uses a special exit code as it doesn't support + abort_on_error. On top, a user may specify a custom AFL_CRASH_EXITCODE. + Handle all three cases here. */ + + if (unlikely( + /* A normal crash/abort */ + (WIFSIGNALED(fsrv->child_status)) || + /* special handling for msan */ + (fsrv->uses_asan && WEXITSTATUS(fsrv->child_status) == MSAN_ERROR) || + /* the custom crash_exitcode was returned by the target */ + (fsrv->uses_crash_exitcode && + WEXITSTATUS(fsrv->child_status) == fsrv->crash_exitcode))) { + + /* For a proper crash, set last_kill_signal to WTERMSIG, else set it to 0 */ + fsrv->last_kill_signal = + WIFSIGNALED(fsrv->child_status) ? WTERMSIG(fsrv->child_status) : 0; return FSRV_RUN_CRASH; } - // Fauxserver should handle this now. - if (*(u32 *)fsrv->trace_bits == EXEC_FAIL_SIG) return FSRV_RUN_ERROR; - + /* success :) */ return FSRV_RUN_OK; } |