diff options
| -rw-r--r-- | include/types.h | 7 | ||||
| -rw-r--r-- | instrumentation/afl-compiler-rt.o.c | 414 | ||||
| -rw-r--r-- | src/afl-forkserver.c | 15 |
3 files changed, 80 insertions, 356 deletions
diff --git a/include/types.h b/include/types.h index d0a2d124..18c5df91 100644 --- a/include/types.h +++ b/include/types.h @@ -52,9 +52,10 @@ typedef uint128_t u128; /* New Forkserver */ #define FS_NEW_VERSION_MIN 1 #define FS_NEW_VERSION_MAX 1 -#define FS_NEW_OPT_MAPSIZE 0x00000001 // parameter: 32 bit value -#define FS_NEW_OPT_SHDMEM_FUZZ 0x00000002 // paramter: none -#define FS_NEW_OPT_AUTODICT 0x00000800 // autodictionary data +#define FS_NEW_ERROR 0xeffe0000 +#define FS_NEW_OPT_MAPSIZE 0x00000001 // parameter: 32 bit value +#define FS_NEW_OPT_SHDMEM_FUZZ 0x00000002 // parameter: none +#define FS_NEW_OPT_AUTODICT 0x00000800 // autodictionary data /* Reporting options */ #define FS_OPT_ENABLED 0x80000001 diff --git a/instrumentation/afl-compiler-rt.o.c b/instrumentation/afl-compiler-rt.o.c index caa3c3a8..c342334c 100644 --- a/instrumentation/afl-compiler-rt.o.c +++ b/instrumentation/afl-compiler-rt.o.c @@ -264,7 +264,7 @@ static void send_forkserver_error(int error) { u32 status; if (!error || error > 0xffff) return; - status = (FS_OPT_ERROR | FS_OPT_SET_ERROR(error)); + status = (FS_NEW_ERROR | error); if (write(FORKSRV_FD + 1, (char *)&status, 4) != 4) { return; } } @@ -367,32 +367,13 @@ static void __afl_map_shm(void) { if ((ptr = getenv("AFL_MAP_SIZE")) != NULL) { val = atoi(ptr); } if (val < __afl_final_loc) { - if (__afl_final_loc > FS_OPT_MAX_MAPSIZE) { + if (__afl_final_loc > MAP_INITIAL_SIZE && !getenv("AFL_QUIET")) { - if (!getenv("AFL_QUIET")) - fprintf(stderr, - "Error: AFL++ tools *require* to set AFL_MAP_SIZE to %u " - "to be able to run this instrumented program!\n", - __afl_final_loc); - - if (id_str) { - - send_forkserver_error(FS_ERROR_MAP_SIZE); - exit(-1); - - } - - } else { - - if (__afl_final_loc > MAP_INITIAL_SIZE && !getenv("AFL_QUIET")) { - - fprintf(stderr, - "Warning: AFL++ tools might need to set AFL_MAP_SIZE to %u " - "to be able to run this instrumented program if this " - "crashes!\n", - __afl_final_loc); - - } + fprintf(stderr, + "Warning: AFL++ tools might need to set AFL_MAP_SIZE to %u " + "to be able to run this instrumented program if this " + "crashes!\n", + __afl_final_loc); } @@ -400,15 +381,6 @@ static void __afl_map_shm(void) { } - } else { - - if (getenv("AFL_DUMP_MAP_SIZE")) { - - printf("%u\n", MAP_SIZE); - exit(-1); - - } - } if (__afl_sharedmem_fuzzing && (!id_str || !getenv(SHM_FUZZ_ENV_VAR) || @@ -474,14 +446,13 @@ static void __afl_map_shm(void) { if (__afl_debug) { - fprintf( - stderr, - "DEBUG: (1) id_str %s, __afl_area_ptr %p, __afl_area_initial %p, " - "__afl_area_ptr_dummy %p, __afl_map_addr 0x%llx, MAP_SIZE %u, " - "__afl_final_loc %u, __afl_map_size %u, max_size_forkserver %u/0x%x\n", - id_str == NULL ? "<null>" : id_str, __afl_area_ptr, __afl_area_initial, - __afl_area_ptr_dummy, __afl_map_addr, MAP_SIZE, __afl_final_loc, - __afl_map_size, FS_OPT_MAX_MAPSIZE, FS_OPT_MAX_MAPSIZE); + fprintf(stderr, + "DEBUG: (1) id_str %s, __afl_area_ptr %p, __afl_area_initial %p, " + "__afl_area_ptr_dummy %p, __afl_map_addr 0x%llx, MAP_SIZE %u, " + "__afl_final_loc %u, __afl_map_size %u\n", + id_str == NULL ? "<null>" : id_str, __afl_area_ptr, + __afl_area_initial, __afl_area_ptr_dummy, __afl_map_addr, MAP_SIZE, + __afl_final_loc, __afl_map_size); } @@ -639,12 +610,10 @@ static void __afl_map_shm(void) { fprintf(stderr, "DEBUG: (2) id_str %s, __afl_area_ptr %p, __afl_area_initial %p, " "__afl_area_ptr_dummy %p, __afl_map_addr 0x%llx, MAP_SIZE " - "%u, __afl_final_loc %u, __afl_map_size %u, " - "max_size_forkserver %u/0x%x\n", + "%u, __afl_final_loc %u, __afl_map_size %u", id_str == NULL ? "<null>" : id_str, __afl_area_ptr, __afl_area_initial, __afl_area_ptr_dummy, __afl_map_addr, MAP_SIZE, - __afl_final_loc, __afl_map_size, FS_OPT_MAX_MAPSIZE, - FS_OPT_MAX_MAPSIZE); + __afl_final_loc, __afl_map_size); } @@ -855,242 +824,6 @@ void write_error_with_location(char *text, char *filename, int linenumber) { } -#ifdef __linux__ -static void __afl_start_snapshots(void) { - - static u8 tmp[4] = {0, 0, 0, 0}; - u32 status = 0; - u32 already_read_first = 0; - u32 was_killed; - - u8 child_stopped = 0; - - void (*old_sigchld_handler)(int) = signal(SIGCHLD, SIG_DFL); - - /* Phone home and tell the parent that we're OK. If parent isn't there, - assume we're not running in forkserver mode and just execute program. */ - - status |= (FS_OPT_ENABLED | FS_OPT_SNAPSHOT | FS_OPT_NEWCMPLOG); - if (__afl_sharedmem_fuzzing) { status |= FS_OPT_SHDMEM_FUZZ; } - if (__afl_map_size <= FS_OPT_MAX_MAPSIZE) - status |= (FS_OPT_SET_MAPSIZE(__afl_map_size) | FS_OPT_MAPSIZE); - if (__afl_dictionary_len && __afl_dictionary) { status |= FS_OPT_AUTODICT; } - memcpy(tmp, &status, 4); - - if (write(FORKSRV_FD + 1, tmp, 4) != 4) { return; } - - if (__afl_sharedmem_fuzzing || (__afl_dictionary_len && __afl_dictionary)) { - - if (read(FORKSRV_FD, &was_killed, 4) != 4) { - - write_error("read to afl-fuzz"); - _exit(1); - - } - - if (__afl_debug) { - - fprintf(stderr, "DEBUG: target forkserver recv: %08x\n", was_killed); - - } - - if ((was_killed & (FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) == - (FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) { - - __afl_map_shm_fuzz(); - - } - - if ((was_killed & (FS_OPT_ENABLED | FS_OPT_AUTODICT)) == - (FS_OPT_ENABLED | FS_OPT_AUTODICT) && - __afl_dictionary_len && __afl_dictionary) { - - // great lets pass the dictionary through the forkserver FD - u32 len = __afl_dictionary_len, offset = 0; - s32 ret; - - if (write(FORKSRV_FD + 1, &len, 4) != 4) { - - write(2, "Error: could not send dictionary len\n", - strlen("Error: could not send dictionary len\n")); - _exit(1); - - } - - while (len != 0) { - - ret = write(FORKSRV_FD + 1, __afl_dictionary + offset, len); - - if (ret < 1) { - - write(2, "Error: could not send dictionary\n", - strlen("Error: could not send dictionary\n")); - _exit(1); - - } - - len -= ret; - offset += ret; - - } - - } else { - - // uh this forkserver does not understand extended option passing - // or does not want the dictionary - if (!__afl_fuzz_ptr) already_read_first = 1; - - } - - } - - while (1) { - - int status; - - if (already_read_first) { - - already_read_first = 0; - - } else { - - /* Wait for parent by reading from the pipe. Abort if read fails. */ - if (read(FORKSRV_FD, &was_killed, 4) != 4) { - - write_error("reading from afl-fuzz"); - _exit(1); - - } - - } - - #ifdef _AFL_DOCUMENT_MUTATIONS - if (__afl_fuzz_ptr) { - - static uint32_t counter = 0; - char fn[32]; - sprintf(fn, "%09u:forkserver", counter); - s32 fd_doc = open(fn, O_WRONLY | O_CREAT | O_TRUNC, DEFAULT_PERMISSION); - if (fd_doc >= 0) { - - if (write(fd_doc, __afl_fuzz_ptr, *__afl_fuzz_len) != *__afl_fuzz_len) { - - fprintf(stderr, "write of mutation file failed: %s\n", fn); - unlink(fn); - - } - - close(fd_doc); - - } - - counter++; - - } - - #endif - - /* If we stopped the child in persistent mode, but there was a race - condition and afl-fuzz already issued SIGKILL, write off the old - process. */ - - if (child_stopped && was_killed) { - - child_stopped = 0; - if (waitpid(child_pid, &status, 0) < 0) { - - write_error("child_stopped && was_killed"); - _exit(1); // TODO why exit? - - } - - } - - if (!child_stopped) { - - /* Once woken up, create a clone of our process. */ - - child_pid = fork(); - if (child_pid < 0) { - - write_error("fork"); - _exit(1); - - } - - /* In child process: close fds, resume execution. */ - - if (!child_pid) { - - //(void)nice(-20); // does not seem to improve - - signal(SIGCHLD, old_sigchld_handler); - signal(SIGTERM, old_sigterm_handler); - - close(FORKSRV_FD); - close(FORKSRV_FD + 1); - - if (!afl_snapshot_take(AFL_SNAPSHOT_MMAP | AFL_SNAPSHOT_FDS | - AFL_SNAPSHOT_REGS | AFL_SNAPSHOT_EXIT)) { - - raise(SIGSTOP); - - } - - __afl_area_ptr[0] = 1; - memset(__afl_prev_loc, 0, NGRAM_SIZE_MAX * sizeof(PREV_LOC_T)); - - return; - - } - - } else { - - /* Special handling for persistent mode: if the child is alive but - currently stopped, simply restart it with SIGCONT. */ - - kill(child_pid, SIGCONT); - child_stopped = 0; - - } - - /* In parent process: write PID to pipe, then wait for child. */ - - if (write(FORKSRV_FD + 1, &child_pid, 4) != 4) { - - write_error("write to afl-fuzz"); - _exit(1); - - } - - if (waitpid(child_pid, &status, WUNTRACED) < 0) { - - write_error("waitpid"); - _exit(1); - - } - - /* In persistent mode, the child stops itself with SIGSTOP to indicate - a successful run. In this case, we want to wake it up without forking - again. */ - - if (WIFSTOPPED(status)) child_stopped = 1; - - /* Relay wait status to pipe, then loop back. */ - - if (write(FORKSRV_FD + 1, &status, 4) != 4) { - - write_error("writing to afl-fuzz"); - _exit(1); - - } - - } - -} - -#endif - /* Fork server logic. */ static void __afl_start_forkserver(void) { @@ -1103,113 +836,92 @@ static void __afl_start_forkserver(void) { old_sigterm_handler = orig_action.sa_handler; signal(SIGTERM, at_exit); -#ifdef __linux__ - if (/*!is_persistent &&*/ !__afl_cmp_map && !getenv("AFL_NO_SNAPSHOT") && - afl_snapshot_init() >= 0) { - - __afl_start_snapshots(); - return; - - } - -#endif - - u8 tmp[4] = {0, 0, 0, 0}; - u32 status_for_fsrv = 0; u32 already_read_first = 0; u32 was_killed; + u32 version = 0x41464c00 + FS_NEW_VERSION_MAX; + u32 tmp = version ^ 0xffffffff, status2, status = version; + u8 *msg = (u8 *)&status; + u8 *reply = (u8 *)&status2; u8 child_stopped = 0; void (*old_sigchld_handler)(int) = signal(SIGCHLD, SIG_DFL); - if (__afl_map_size <= FS_OPT_MAX_MAPSIZE) { - - status_for_fsrv |= (FS_OPT_SET_MAPSIZE(__afl_map_size) | FS_OPT_MAPSIZE); + /* Phone home and tell the parent that we're OK. If parent isn't there, + assume we're not running in forkserver mode and just execute program. */ - } + // return because possible non-forkserver usage + if (write(FORKSRV_FD + 1, msg, 4) != 4) { return; } - if (__afl_dictionary_len && __afl_dictionary) { + if (read(FORKSRV_FD, reply, 4) != 4) { _exit(1); } + if (tmp != status2) { - status_for_fsrv |= FS_OPT_AUTODICT; + write_error("wrong forkserver message from AFL++ tool"); + _exit(1); } - if (__afl_sharedmem_fuzzing) { status_for_fsrv |= FS_OPT_SHDMEM_FUZZ; } - if (status_for_fsrv) { + // send the set/requested options to forkserver + status = FS_NEW_OPT_MAPSIZE; // we always send the map size + if (__afl_sharedmem_fuzzing) { status |= FS_NEW_OPT_SHDMEM_FUZZ; } + if (__afl_dictionary_len && __afl_dictionary) { - status_for_fsrv |= (FS_OPT_ENABLED | FS_OPT_NEWCMPLOG); + status |= FS_NEW_OPT_AUTODICT; } - memcpy(tmp, &status_for_fsrv, 4); + if (write(FORKSRV_FD + 1, msg, 4) != 4) { _exit(1); } - /* Phone home and tell the parent that we're OK. If parent isn't there, - assume we're not running in forkserver mode and just execute program. */ - - if (write(FORKSRV_FD + 1, tmp, 4) != 4) { return; } - - __afl_connected = 1; + // Now send the parameters for the set options, increasing by option number - if (__afl_sharedmem_fuzzing || (__afl_dictionary_len && __afl_dictionary)) { + // FS_NEW_OPT_MAPSIZE - we always send the map size + status = __afl_map_size; + if (write(FORKSRV_FD + 1, msg, 4) != 4) { _exit(1); } - if (read(FORKSRV_FD, &was_killed, 4) != 4) _exit(1); + // FS_NEW_OPT_SHDMEM_FUZZ - no data - if (__afl_debug) { - - fprintf(stderr, "DEBUG: target forkserver recv: %08x\n", was_killed); + // FS_NEW_OPT_AUTODICT - send autodictionary + if (__afl_dictionary_len && __afl_dictionary) { - } + // pass the dictionary through the forkserver FD + u32 len = __afl_dictionary_len, offset = 0; - if ((was_killed & (FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) == - (FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) { + if (write(FORKSRV_FD + 1, &len, 4) != 4) { - __afl_map_shm_fuzz(); + write(2, "Error: could not send dictionary len\n", + strlen("Error: could not send dictionary len\n")); + _exit(1); } - if ((was_killed & (FS_OPT_ENABLED | FS_OPT_AUTODICT)) == - (FS_OPT_ENABLED | FS_OPT_AUTODICT) && - __afl_dictionary_len && __afl_dictionary) { + while (len != 0) { - // great lets pass the dictionary through the forkserver FD - u32 len = __afl_dictionary_len, offset = 0; + s32 ret; + ret = write(FORKSRV_FD + 1, __afl_dictionary + offset, len); - if (write(FORKSRV_FD + 1, &len, 4) != 4) { + if (ret < 1) { - write(2, "Error: could not send dictionary len\n", - strlen("Error: could not send dictionary len\n")); + write_error("could not send dictionary"); _exit(1); } - while (len != 0) { - - s32 ret; - ret = write(FORKSRV_FD + 1, __afl_dictionary + offset, len); - - if (ret < 1) { - - write(2, "Error: could not send dictionary\n", - strlen("Error: could not send dictionary\n")); - _exit(1); - - } + len -= ret; + offset += ret; - len -= ret; - offset += ret; + } - } + } - } else { + // send welcome message as final message + status = version; + if (write(FORKSRV_FD + 1, msg, 4) != 4) { _exit(1); } - // uh this forkserver does not understand extended option passing - // or does not want the dictionary - if (!__afl_fuzz_ptr) already_read_first = 1; + // END forkserver handshake - } + __afl_connected = 1; - } + if (__afl_sharedmem_fuzzing) { __afl_map_shm_fuzz(); } while (1) { @@ -1225,7 +937,7 @@ static void __afl_start_forkserver(void) { if (read(FORKSRV_FD, &was_killed, 4) != 4) { - // write_error("read from afl-fuzz"); + write_error("read from AFL++ tool"); _exit(1); } diff --git a/src/afl-forkserver.c b/src/afl-forkserver.c index 1f796e53..a3a869d7 100644 --- a/src/afl-forkserver.c +++ b/src/afl-forkserver.c @@ -1030,6 +1030,12 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, * send any data anymore - except a future option requires this. */ + if ((status & FS_NEW_ERROR) == FS_NEW_ERROR) { + + report_error_and_exit(status & 0x0000ffff); + + } + if (status >= 0x41464c00 && status <= 0x41464cff) { u32 version = status - 0x41464c00; @@ -1047,6 +1053,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, } + u32 keep = status; status ^= 0xffffffff; if (write(fsrv->fsrv_ctl_fd, &status, 4) != 4) { @@ -1064,7 +1071,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, if (getenv("AFL_DEBUG")) { - ACTF("Forkserver options received: (%08x)", status); + ACTF("Forkserver options received: (0x%08x)", status); } @@ -1178,7 +1185,11 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv, u32 status2; rlen = read(fsrv->fsrv_st_fd, &status2, 4); - if (status2 != status) { FATAL("Error in forkserver communication"); } + if (status2 != keep) { + + FATAL("Error in forkserver communication (%08x=>%08x)", keep, status2); + + } } else { |