ExternalVendorCode/AFLplusplus
1
0
Fork 0
mirror of https://github.com/AFLplusplus/AFLplusplus.git synced 2025-06-14 02:58:08 +00:00
Code Issues Packages Projects Releases Wiki Activity

more refactoring and update changelog

Browse Source
This commit is contained in:
van Hauser
2020-04-11 08:02:54 +02:00
parent 8bcfba8231
commit 32ba60185e
13 changed files with 50 additions and 490 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
docs/Changelog.md
View File

@ -10,7 +10,16 @@ sending a mail to <afl-users+subscribe@googlegroups.com>.
### Version ++2.63d (development):
- LTO mode now requires llvm11 - but compiles all targets! :)
- llvm_mode LTO mode:
- now requires llvm11 - but compiles all targets! :)
- autodictionary feature added, enable with AFL_LLVM_LTO_AUTODICTIONARY
- variable map size usage
- afl-fuzz:
- variable map size support added (only LTO mode can use this)
- snapshot feature usage now visible in UI
- extended forkserver: map_size and more information is communicated to
afl-fuzz (and afl-fuzz acts accordingly)
- more refactoring
- if AFL_CC/AFL_CXX is set but empty afl compilers did fail, fixed
(this bug is in vanilla afl too)

5
include/afl-fuzz.h
View File

@ -331,7 +331,8 @@ typedef struct afl_env_vars {
u8 afl_skip_cpufreq, afl_exit_when_done, afl_no_affinity, afl_skip_bin_check,
afl_dumb_forksrv, afl_import_first, afl_custom_mutator_only, afl_no_ui,
afl_force_ui, afl_i_dont_care_about_missing_crashes, afl_bench_just_one,
afl_bench_until_crash, afl_debug_child_output, afl_autoresume;
afl_bench_until_crash, afl_debug_child_output, afl_autoresume,
afl_cal_fast;
u8 *afl_tmpdir, *afl_post_library, *afl_custom_mutator_library,
*afl_python_module, *afl_path, *afl_hang_tmout, *afl_skip_crashes,
@ -558,7 +559,7 @@ typedef struct afl_state {
/* CmpLog */
char *cmplog_binary;
char * cmplog_binary;
afl_forkserver_t cmplog_fsrv; /* cmplog has its own little forkserver */
/* Custom mutators */

1
include/cmplog.h
View File

@ -79,6 +79,5 @@ struct cmp_map {
void cmplog_exec_child(afl_forkserver_t *fsrv, char **argv);
#endif

1
src/afl-forkserver.c
View File

@ -187,6 +187,7 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv,
FATAL("Different forkserver not compatible with fauxserver");
fsrv->init_child_func = afl_fauxsrv_execv;
}
if (pipe(st_pipe) || pipe(ctl_pipe)) PFATAL("pipe() failed");

469
src/afl-fuzz-cmplog.c
View File

@ -30,6 +30,7 @@
#include "cmplog.h"
typedef struct cmplog_data {
} cmplog_data_t;
void cmplog_exec_child(afl_forkserver_t *fsrv, char **argv) {
@ -38,479 +39,12 @@ void cmplog_exec_child(afl_forkserver_t *fsrv, char **argv) {
if (!fsrv->qemu_mode && argv[0] != fsrv->cmplog_binary) {
#if 0
afl->fsrv.child_timed_out = 0;
afl->cmplog_fsrv_pid = fork();
if (afl->cmplog_fsrv_pid < 0) PFATAL("fork() failed");
if (!afl->cmplog_fsrv_pid) {
/* CHILD PROCESS */
struct rlimit r;
/* Umpf. On OpenBSD, the default fd limit for root users is set to
soft 128. Let's try to fix that... */
if (!getrlimit(RLIMIT_NOFILE, &r) && r.rlim_cur < FORKSRV_FD + 2) {
r.rlim_cur = FORKSRV_FD + 2;
setrlimit(RLIMIT_NOFILE, &r); /* Ignore errors */
}
if (afl->fsrv.mem_limit) {
r.rlim_max = r.rlim_cur = ((rlim_t)afl->fsrv.mem_limit) << 20;
#ifdef RLIMIT_AS
setrlimit(RLIMIT_AS, &r); /* Ignore errors */
#else
/* This takes care of OpenBSD, which doesn't have RLIMIT_AS, but
according to reliable sources, RLIMIT_DATA covers anonymous
maps - so we should be getting good protection against OOM bugs. */
setrlimit(RLIMIT_DATA, &r); /* Ignore errors */
#endif /* ^RLIMIT_AS */
}
/* Dumping cores is slow and can lead to anomalies if SIGKILL is delivered
before the dump is complete. */
// r.rlim_max = r.rlim_cur = 0;
// setrlimit(RLIMIT_CORE, &r); /* Ignore errors */
/* Isolate the process and configure standard descriptors. If
afl->fsrv.out_file is specified, stdin is /dev/null; otherwise,
afl->fsrv.out_fd is cloned instead. */
setsid();
if (!(afl->afl_env.afl_debug_child_output)) {
dup2(afl->fsrv.dev_null_fd, 1);
dup2(afl->fsrv.dev_null_fd, 2);
}
if (!afl->fsrv.use_stdin) {
dup2(afl->fsrv.dev_null_fd, 0);
} else {
dup2(afl->fsrv.out_fd, 0);
close(afl->fsrv.out_fd);
}
/* Set up control and status pipes, close the unneeded original fds. */
if (dup2(ctl_pipe[0], FORKSRV_FD) < 0) PFATAL("dup2() failed");
if (dup2(st_pipe[1], FORKSRV_FD + 1) < 0) PFATAL("dup2() failed");
close(ctl_pipe[0]);
close(ctl_pipe[1]);
close(st_pipe[0]);
close(st_pipe[1]);
close(afl->fsrv.out_dir_fd);
close(afl->fsrv.dev_null_fd);
#ifndef HAVE_ARC4RANDOM
close(afl->fsrv.dev_urandom_fd);
#endif
if (afl->fsrv.plot_file != NULL) fclose(afl->fsrv.plot_file);
/* This should improve performance a bit, since it stops the linker from
doing extra work post-fork(). */
if (!getenv("LD_BIND_LAZY")) setenv("LD_BIND_NOW", "1", 0);
/* Set sane defaults for ASAN if nothing else specified. */
setenv("ASAN_OPTIONS",
"abort_on_error=1:"
"detect_leaks=0:"
"malloc_context_size=0:"
"symbolize=0:"
"allocator_may_return_null=1",
0);
/* MSAN is tricky, because it doesn't support abort_on_error=1 at this
point. So, we do this in a very hacky way. */
setenv("MSAN_OPTIONS",
"exit_code=" STRINGIFY(MSAN_ERROR) ":"
"symbolize=0:"
"abort_on_error=1:"
"malloc_context_size=0:"
"allocator_may_return_null=1:"
"msan_track_origins=0",
0);
setenv("___AFL_EINS_ZWEI_POLIZEI___", "1", 1);
if (!afl->qemu_mode && afl->argv[0] != afl->cmplog_binary) {
ck_free(afl->argv[0]);
afl->argv[0] = afl->cmplog_binary;
}
execv(afl->argv[0], afl->argv);
/* Use a distinctive bitmap signature to tell the parent about execv()
falling through. */
*(u32 *)afl->fsrv.trace_bits = EXEC_FAIL_SIG;
exit(0);
}
/* PARENT PROCESS */
/* Close the unneeded endpoints. */
close(ctl_pipe[0]);
close(st_pipe[1]);
afl->cmplog_fsrv_ctl_fd = ctl_pipe[1];
afl->cmplog_fsrv_st_fd = st_pipe[0];
/* Wait for the fork server to come up, but don't wait too long. */
rlen = 0;
if (afl->fsrv.exec_tmout) {
rlen = 4;
u32 timeout_ms = afl->fsrv.exec_tmout * FORK_WAIT_MULT;
/* Reuse readfds as exceptfds to see when the child closed the pipe */
u32 exec_ms = read_timed(afl->cmplog_fsrv_st_fd, &status, rlen, timeout_ms,
&afl->stop_soon);
if (!exec_ms) {
PFATAL("Error in timed read");
} else if (exec_ms > timeout_ms) {
afl->fsrv.child_timed_out = 1;
kill(afl->cmplog_fsrv_pid, SIGKILL);
rlen = read(afl->cmplog_fsrv_st_fd, &status, 4);
}
} else {
rlen = read(afl->cmplog_fsrv_st_fd, &status, 4);
}
/* If we have a four-byte "hello" message from the server, we're all set.
Otherwise, try to figure out what went wrong. */
if (afl->fsrv.child_timed_out)
FATAL(
"Timeout while initializing cmplog fork server (adjusting -t may "
"help)");
if (rlen == 4) {
OKF("All right - fork server is up.");
return;
}
if (waitpid(afl->cmplog_fsrv_pid, &status, 0) <= 0)
PFATAL("waitpid() failed");
if (WIFSIGNALED(status)) {
if (afl->fsrv.mem_limit && afl->fsrv.mem_limit < 500 &&
afl->fsrv.uses_asan) {
SAYF("\n" cLRD "[-] " cRST
"Whoops, the target binary crashed suddenly, "
"before receiving any input\n"
" from the fuzzer! Since it seems to be built with ASAN and you "
"have a\n"
" restrictive memory limit configured, this is expected; please "
"read\n"
" %s/notes_for_asan.md for help.\n",
doc_path);
} else if (!afl->fsrv.mem_limit) {
SAYF("\n" cLRD "[-] " cRST
"Whoops, the target binary crashed suddenly, "
"before receiving any input\n"
" from the fuzzer! There are several probable explanations:\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 "
"replacement.\n\n"
MSG_FORK_ON_APPLE
" - Less likely, there is a horrible bug in the fuzzer. If other "
"options\n"
" fail, poke <afl-users@googlegroups.com> for troubleshooting "
"tips.\n");
} else {
u8 val_buf[STRINGIFY_VAL_SIZE_MAX];
SAYF("\n" cLRD "[-] " cRST
"Whoops, the target binary crashed suddenly, "
"before receiving any input\n"
" from the fuzzer! There are several probable explanations:\n\n"
" - The current memory limit (%s) is too restrictive, causing "
"the\n"
" target to hit an OOM condition in the dynamic linker. Try "
"bumping up\n"
" the limit with the -m setting in the command line. A simple "
"way confirm\n"
" this diagnosis would be:\n\n"
MSG_ULIMIT_USAGE
" /path/to/fuzzed_app )\n\n"
" Tip: you can use http://jwilk.net/software/recidivm to "
"quickly\n"
" estimate the required amount of virtual memory for the "
"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 "
"replacement.\n\n"
MSG_FORK_ON_APPLE
" - Less likely, there is a horrible bug in the fuzzer. If other "
"options\n"
" fail, poke <afl-users@googlegroups.com> for troubleshooting "
"tips.\n",
stringify_mem_size(val_buf, sizeof(val_buf),
afl->fsrv.mem_limit << 20),
afl->fsrv.mem_limit - 1);
}
FATAL("Cmplog fork server crashed with signal %d", WTERMSIG(status));
}
if (*(u32 *)afl->fsrv.trace_bits == EXEC_FAIL_SIG)
FATAL("Unable to execute target application ('%s')", afl->argv[0]);
if (afl->fsrv.mem_limit && afl->fsrv.mem_limit < 500 && afl->fsrv.uses_asan) {
SAYF("\n" cLRD "[-] " cRST
"Hmm, looks like the target binary terminated "
"before we could complete a\n"
" handshake with the injected code. Since it seems to be built "
"with ASAN and\n"
" you have a restrictive memory limit configured, this is "
"expected; please\n"
" read %s/notes_for_asan.md for help.\n",
doc_path);
} else if (!afl->fsrv.mem_limit) {
SAYF("\n" cLRD "[-] " cRST
"Hmm, looks like the target binary terminated "
"before we could complete a\n"
" handshake with the injected code. Perhaps there is a horrible "
"bug in the\n"
" fuzzer. Poke <afl-users@googlegroups.com> for troubleshooting "
"tips.\n");
} else {
u8 val_buf[STRINGIFY_VAL_SIZE_MAX];
SAYF(
"\n" cLRD "[-] " cRST
"Hmm, looks like the target binary terminated "
"before we could complete a\n"
" handshake with the injected code. There are %s probable "
"explanations:\n\n"
"%s"
" - The current memory limit (%s) is too restrictive, causing an "
"OOM\n"
" fault in the dynamic linker. This can be fixed with the -m "
"option. A\n"
" simple way to confirm the diagnosis may be:\n\n"
MSG_ULIMIT_USAGE
" /path/to/fuzzed_app )\n\n"
" Tip: you can use http://jwilk.net/software/recidivm to quickly\n"
" estimate the required amount of virtual memory for the "
"binary.\n\n"
" - Less likely, there is a horrible bug in the fuzzer. If other "
"options\n"
" fail, poke <afl-users@googlegroups.com> for troubleshooting "
"tips.\n",
getenv(DEFER_ENV_VAR) ? "three" : "two",
getenv(DEFER_ENV_VAR)
? " - You are using deferred forkserver, but __AFL_INIT() is "
"never\n"
" reached before the program terminates.\n\n"
: "",
stringify_mem_size(val_buf, sizeof(val_buf), afl->fsrv.mem_limit << 20),
afl->fsrv.mem_limit - 1);
}
FATAL("Cmplog fork server handshake failed");
}
u8 run_cmplog_target(afl_state_t *afl, u32 timeout) {
int status = 0;
u32 exec_ms;
u32 tb4;
s32 res;
afl->fsrv.child_timed_out = 0;
/* After this memset, afl->fsrv.trace_bits[] are effectively volatile, so we
must prevent any earlier operations from venturing into that
territory. */
memset(afl->fsrv.trace_bits, 0, afl->fsrv.map_size);
MEM_BARRIER();
/* Since we always have a forkserver (or a fauxserver) running, we can simply
tell them to have at it and read back the pid from it.*/
if ((res = write(afl->cmplog_fsrv_ctl_fd, &afl->cmplog_prev_timed_out, 4)) !=
4) {
if (afl->stop_soon) return 0;
RPFATAL(res,
"Unable to request new process from cmplog fork server (OOM?)");
}
if ((res = read(afl->cmplog_fsrv_st_fd, &afl->cmplog_child_pid, 4)) != 4) {
if (afl->stop_soon) return 0;
RPFATAL(res,
"Unable to request new process from cmplog fork server (OOM?)");
}
if (afl->cmplog_child_pid <= 0)
FATAL("Cmplog fork server is misbehaving (OOM?)");
/* Configure timeout, as requested by user, then wait for child to terminate.
*/
exec_ms =
read_timed(afl->cmplog_fsrv_st_fd, &status, 4, timeout, &afl->stop_soon);
if (exec_ms > timeout) {
/* If there was no response from forkserver after timeout seconds,
we kill the child. The forkserver should inform us afterwards */
kill(afl->cmplog_child_pid, SIGKILL);
afl->fsrv.child_timed_out = 1;
/* After killing the child, the forkserver should tell us */
if (!read(afl->cmplog_fsrv_st_fd, &status, 4)) exec_ms = 0;
}
if (!exec_ms) { // Something went wrong.
if (afl->stop_soon) return 0;
SAYF("\n" cLRD "[-] " cRST
"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"
" - The binary or one of the libraries it uses manages to create\n"
" threads before the forkserver initializes.\n"
" - The binary, at least in some circumstances, exits in a way "
"that\n"
" also kills the parent process - raise() could be the "
"culprit.\n\n"
"If all else fails you can disable the fork server via "
"AFL_NO_FORKSRV=1.\n",
afl->fsrv.mem_limit);
RPFATAL(res, "Unable to communicate with fork server");
}
if (!WIFSTOPPED(status)) afl->cmplog_child_pid = 0;
if (afl->slowest_exec_ms < exec_ms) afl->slowest_exec_ms = exec_ms;
++afl->total_execs;
/* Any subsequent operations on afl->fsrv.trace_bits must not be moved by the
compiler below this point. Past this location, afl->fsrv.trace_bits[]
behave very normally and do not have to be treated as volatile. */
MEM_BARRIER();
tb4 = *(u32 *)afl->fsrv.trace_bits;
#ifdef WORD_SIZE_64
classify_counts(afl, (u64 *)afl->fsrv.trace_bits);
#else
classify_counts(afl, (u32 *)afl->fsrv.trace_bits);
#endif /* ^WORD_SIZE_64 */
afl->cmplog_prev_timed_out = afl->fsrv.child_timed_out;
/* Report outcome to caller. */
if (WIFSIGNALED(status) && !afl->stop_soon) {
afl->kill_signal = WTERMSIG(status);
if (afl->fsrv.child_timed_out && afl->kill_signal == SIGKILL)
return FAULT_TMOUT;
return FAULT_CRASH;
}
/* A somewhat nasty hack for MSAN, which doesn't support abort_on_error and
must use a special exit code. */
if (afl->fsrv.uses_asan && WEXITSTATUS(status) == MSAN_ERROR) {
afl->kill_signal = 0;
return FAULT_CRASH;
}
if ((afl->dumb_mode == 1 || afl->no_forkserver) && tb4 == EXEC_FAIL_SIG)
return FAULT_ERROR;
return FAULT_NONE;
#else
ck_free(argv[0]);
argv[0] = fsrv->cmplog_binary;
}
execv(argv[0], argv);
#endif
}
@ -571,3 +105,4 @@ u8 common_fuzz_cmplog_stuff(afl_state_t *afl, u8 *out_buf, u32 len) {
return 0;
}

6
src/afl-fuzz-mutators.c
View File

@ -34,7 +34,7 @@ void load_custom_mutator_py(afl_state_t *, char *);
void setup_custom_mutator(afl_state_t *afl) {
/* Try mutator library first */
u8 *fn = getenv("AFL_CUSTOM_MUTATOR_LIBRARY");
u8 *fn = afl->afl_env.afl_custom_mutator_library;
if (fn) {
@ -52,7 +52,7 @@ void setup_custom_mutator(afl_state_t *afl) {
/* Try Python module */
#ifdef USE_PYTHON
u8 *module_name = getenv("AFL_PYTHON_MODULE");
u8 *module_name = afl->afl_env.afl_python_module;
if (module_name) {
@ -67,7 +67,7 @@ void setup_custom_mutator(afl_state_t *afl) {
}
#else
if (getenv("AFL_PYTHON_MODULE"))
if (afl->afl_env.afl_python_module)
FATAL("Your AFL binary was built without Python support");
#endif

14
src/afl-fuzz-run.c
View File

@ -69,8 +69,7 @@ u8 run_target(afl_state_t *afl, afl_forkserver_t *fsrv, u32 timeout) {
if (fsrv->child_pid <= 0) FATAL("Fork server is misbehaving (OOM?)");
exec_ms =
read_timed(fsrv->fsrv_st_fd, &status, 4, timeout, &afl->stop_soon);
exec_ms = read_timed(fsrv->fsrv_st_fd, &status, 4, timeout, &afl->stop_soon);
if (exec_ms > timeout) {
@ -312,10 +311,17 @@ u8 calibrate_case(afl_state_t *afl, struct queue_entry *q, u8 *use_mem,
count its spin-up time toward binary calibration. */
if (!afl->fsrv.fsrv_pid) {
if (afl->shm.cmplog_mode && afl->fsrv.init_child_func != cmplog_exec_child) {
if (afl->shm.cmplog_mode &&
afl->fsrv.init_child_func != cmplog_exec_child) {
FATAL("BUG in afl-fuzz detected. Cmplog mode not set correctly.");
}
afl_fsrv_start(&afl->fsrv, afl->argv, &afl->stop_soon, afl->afl_env.afl_debug_child_output);
afl_fsrv_start(&afl->fsrv, afl->argv, &afl->stop_soon,
afl->afl_env.afl_debug_child_output);
}
if (q->exec_cksum)

7
src/afl-fuzz-state.c
View File

@ -284,6 +284,13 @@ void read_afl_environment(afl_state_t *afl, char **envp) {
afl->afl_env.afl_autoresume =
get_afl_env(afl_environment_variables[i]) ? 1 : 0;
} else if (!strncmp(env, "AFL_CAL_FAST",
afl_environment_variable_len)) {
afl->afl_env.afl_cal_fast =
get_afl_env(afl_environment_variables[i]) ? 1 : 0;
} else if (!strncmp(env, "AFL_TMPDIR",
afl_environment_variable_len)) {

10
src/afl-fuzz.c
View File

@ -248,6 +248,7 @@ int main(int argc, char **argv_orig, char **envp) {
afl_state_init(afl);
afl_fsrv_init(&afl->fsrv);
if (get_afl_env("AFL_DEBUG")) afl->debug = 1;
read_afl_environment(afl, envp);
exit_1 = !!afl->afl_env.afl_bench_just_one;
@ -690,7 +691,7 @@ int main(int argc, char **argv_orig, char **envp) {
OKF("MOpt Mutator from github.com/puppet-meteor/MOpt-AFL");
if (afl->sync_id && afl->force_deterministic &&
getenv("AFL_CUSTOM_MUTATOR_ONLY"))
afl->afl_env.afl_custom_mutator_only)
WARNF(
"Using -M master with the AFL_CUSTOM_MUTATOR_ONLY mutator options will "
"result in no deterministic mutations being done!");
@ -865,7 +866,7 @@ int main(int argc, char **argv_orig, char **envp) {
check_if_tty(afl);
if (afl->afl_env.afl_force_ui) afl->not_on_tty = 0;
if (get_afl_env("AFL_CAL_FAST")) {
if (afl->afl_env.afl_cal_fast) {
/* Use less calibration cycles, for slow applications */
afl->cal_cycles = 3;
@ -873,8 +874,6 @@ int main(int argc, char **argv_orig, char **envp) {
}
if (get_afl_env("AFL_DEBUG")) afl->debug = 1;
if (afl->afl_env.afl_custom_mutator_only) {
/* This ensures we don't proceed to havoc/splice */
@ -1024,7 +1023,8 @@ int main(int argc, char **argv_orig, char **envp) {
SAYF("Spawning cmplog forkserver");
memcpy(&afl->cmplog_fsrv, &afl->fsrv, sizeof(afl->fsrv));
afl->cmplog_fsrv.init_child_func = cmplog_exec_child;
afl_fsrv_start(&afl->cmplog_fsrv, afl->argv, &afl->stop_soon, afl->afl_env.afl_debug_child_output);
afl_fsrv_start(&afl->cmplog_fsrv, afl->argv, &afl->stop_soon,
afl->afl_env.afl_debug_child_output);
}

3
src/afl-showmap.c
View File

@ -949,7 +949,8 @@ int main(int argc, char **argv_orig, char **envp) {
}
afl_fsrv_start(fsrv, use_argv, &stop_soon, get_afl_env("AFL_DEBUG_CHILD_OUTPUT")? 1 :0);
afl_fsrv_start(fsrv, use_argv, &stop_soon,
get_afl_env("AFL_DEBUG_CHILD_OUTPUT") ? 1 : 0);
while (done == 0 && (dir_ent = readdir(dir_in))) {

3
src/afl-tmin.c
View File

@ -1131,7 +1131,8 @@ int main(int argc, char **argv_orig, char **envp) {
read_initial_file();
afl_fsrv_start(fsrv, use_argv, &stop_soon, get_afl_env("AFL_DEBUG_CHILD_OUTPUT")? 1 :0);
afl_fsrv_start(fsrv, use_argv, &stop_soon,
get_afl_env("AFL_DEBUG_CHILD_OUTPUT") ? 1 : 0);
ACTF("Performing dry run (mem limit = %llu MB, timeout = %u ms%s)...",
fsrv->mem_limit, fsrv->exec_tmout, edges_only ? ", edges only" : "");