From ef311ec70cd9f58cc58fe67fd693d94e01edbf98 Mon Sep 17 00:00:00 2001 From: van Hauser Date: Fri, 17 Apr 2020 10:08:56 +0200 Subject: done implementing AFL_MAP_SIZE --- llvm_mode/afl-clang-fast.c | 10 ++++++++++ llvm_mode/afl-llvm-lto-instrumentation.so.cc | 28 +++++++++++++++------------- 2 files changed, 25 insertions(+), 13 deletions(-) (limited to 'llvm_mode') diff --git a/llvm_mode/afl-clang-fast.c b/llvm_mode/afl-clang-fast.c index c0471033..5abe61c6 100644 --- a/llvm_mode/afl-clang-fast.c +++ b/llvm_mode/afl-clang-fast.c @@ -796,6 +796,16 @@ int main(int argc, char **argv, char **envp) { } + u8 *ptr2; + if (!be_quiet && instrument_mode != INSTRUMENT_LTO && + ((ptr2 = getenv("AFL_MAP_SIZE")) || (ptr2 = getenv("AFL_MAPSIZE")))) { + + u32 map_size = atoi(ptr2); + if (map_size != MAP_SIZE) + FATAL("AFL_MAP_SIZE is not supported by afl-clang-fast"); + + } + if (debug) { SAYF(cMGN "[D]" cRST " cd \"%s\";", getthecwd()); diff --git a/llvm_mode/afl-llvm-lto-instrumentation.so.cc b/llvm_mode/afl-llvm-lto-instrumentation.so.cc index c5e7a2b7..a5058974 100644 --- a/llvm_mode/afl-llvm-lto-instrumentation.so.cc +++ b/llvm_mode/afl-llvm-lto-instrumentation.so.cc @@ -608,20 +608,22 @@ bool AFLLTOPass::runOnModule(Module &M) { } - // save highest location ID to global variable - // do this after each function to fail faster - if (afl_global_id > MAP_SIZE) { - - uint32_t pow2map = 1, map = afl_global_id; - while ((map = map >> 1)) - pow2map++; - FATAL( - "We have %u blocks to instrument but the map size is only %u! Edit " - "config.h and set MAP_SIZE_POW2 from %u to %u, then recompile " - "afl-fuzz and llvm_mode.", - afl_global_id, MAP_SIZE, MAP_SIZE_POW2, pow2map); + } - } + // save highest location ID to global variable + // do this after each function to fail faster + if (!be_quiet && afl_global_id > MAP_SIZE) { + + uint32_t pow2map = 1, map = afl_global_id; + while ((map = map >> 1)) + pow2map++; + WARNF( + "We have %u blocks to instrument but the map size is only %u. Either " + "edit config.h and set MAP_SIZE_POW2 from %u to %u, then recompile " + "afl-fuzz and llvm_mode and then make this target - or set " + "AFL_MAP_SIZE with at least size %u when running afl-fuzz with this " + "target.", + afl_global_id, MAP_SIZE, MAP_SIZE_POW2, pow2map, afl_global_id); } -- cgit 1.4.1 From 248a2f2f0bfddd9f79a4c6b6ceadef32f1765969 Mon Sep 17 00:00:00 2001 From: van Hauser Date: Fri, 17 Apr 2020 10:21:41 +0200 Subject: added AFL_MAP_SIZE to env help output --- llvm_mode/afl-clang-fast.c | 50 +++++++++++++++++++++++----------------------- src/afl-analyze.c | 4 +++- src/afl-fuzz.c | 50 ++++++++++++++++++++++++---------------------- src/afl-showmap.c | 11 ++++++---- src/afl-tmin.c | 4 +++- 5 files changed, 64 insertions(+), 55 deletions(-) (limited to 'llvm_mode') diff --git a/llvm_mode/afl-clang-fast.c b/llvm_mode/afl-clang-fast.c index 5abe61c6..7466db26 100644 --- a/llvm_mode/afl-clang-fast.c +++ b/llvm_mode/afl-clang-fast.c @@ -716,30 +716,30 @@ int main(int argc, char **argv, char **envp) { "Environment variables used:\n" "AFL_CC: path to the C compiler to use\n" "AFL_CXX: path to the C++ compiler to use\n" - "AFL_PATH: path to instrumenting pass and runtime " - "(afl-llvm-rt.*o)\n" - "AFL_DONT_OPTIMIZE: disable optimization instead of -O3\n" - "AFL_NO_BUILTIN: compile for use with libtokencap.so\n" - "AFL_INST_RATIO: percentage of branches to instrument\n" - "AFL_QUIET: suppress verbose output\n" "AFL_DEBUG: enable developer debugging output\n" + "AFL_DONT_OPTIMIZE: disable optimization instead of -O3\n" "AFL_HARDEN: adds code hardening to catch memory bugs\n" - "AFL_USE_ASAN: activate address sanitizer\n" - "AFL_USE_MSAN: activate memory sanitizer\n" - "AFL_USE_UBSAN: activate undefined behaviour sanitizer\n" - "AFL_USE_CFISAN: activate control flow sanitizer\n" - "AFL_LLVM_WHITELIST: enable whitelisting (selective " - "instrumentation)\n" + "AFL_INST_RATIO: percentage of branches to instrument\n" "AFL_LLVM_NOT_ZERO: use cycling trace counters that skip zero\n" "AFL_LLVM_LAF_SPLIT_COMPARES: enable cascaded comparisons\n" - "AFL_LLVM_LAF_SPLIT_SWITCHES: casc. comp. in 'switch'\n" - "AFL_LLVM_LAF_TRANSFORM_COMPARES: transform library comparison " - "function calls\n" - " to cascaded comparisons\n" "AFL_LLVM_LAF_SPLIT_FLOATS: transform floating point comp. to " "cascaded " "comp.\n" - "AFL_LLVM_LAF_SPLIT_COMPARES_BITW: size limit (default 8)\n", + "AFL_LLVM_LAF_SPLIT_SWITCHES: casc. comp. in 'switch'\n" + " to cascaded comparisons\n" + "AFL_LLVM_LAF_TRANSFORM_COMPARES: transform library comparison " + "function calls\n" + "AFL_LLVM_LAF_SPLIT_COMPARES_BITW: size limit (default 8)\n" + "AFL_LLVM_WHITELIST: enable whitelisting (selective " + "instrumentation)\n" + "AFL_NO_BUILTIN: compile for use with libtokencap.so\n" + "AFL_PATH: path to instrumenting pass and runtime " + "(afl-llvm-rt.*o)\n" + "AFL_QUIET: suppress verbose output\n" + "AFL_USE_ASAN: activate address sanitizer\n" + "AFL_USE_CFISAN: activate control flow sanitizer\n" + "AFL_USE_MSAN: activate memory sanitizer\n" + "AFL_USE_UBSAN: activate undefined behaviour sanitizer\n", callname, BIN_PATH, BIN_PATH); SAYF( @@ -747,21 +747,21 @@ int main(int argc, char **argv, char **envp) { "AFL_LLVM_CMPLOG: log operands of comparisons (RedQueen mutator)\n" "AFL_LLVM_INSTRUMENT: set instrumentation mode: DEFAULT, CFG " "(INSTRIM), LTO, CTX, NGRAM-2 ... NGRAM-16\n" - "You can also use the old environment variables:" - "AFL_LLVM_CTX: use context sensitive coverage\n" - "AFL_LLVM_USE_TRACE_PC: use LLVM trace-pc-guard instrumentation\n" - "AFL_LLVM_NGRAM_SIZE: use ngram prev_loc count coverage\n" - "AFL_LLVM_INSTRIM: use light weight instrumentation InsTrim\n" - "AFL_LLVM_INSTRIM_LOOPHEAD: optimize loop tracing for speed (sub " + " You can also use the old environment variables instead:" + " AFL_LLVM_CTX: use context sensitive coverage\n" + " AFL_LLVM_USE_TRACE_PC: use LLVM trace-pc-guard instrumentation\n" + " AFL_LLVM_NGRAM_SIZE: use ngram prev_loc count coverage\n" + " AFL_LLVM_INSTRIM: use light weight instrumentation InsTrim\n" + " AFL_LLVM_INSTRIM_LOOPHEAD: optimize loop tracing for speed (sub " "option to INSTRIM)\n"); #ifdef AFL_CLANG_FLTO SAYF( "\nafl-clang-lto specific environment variables:\n" - "AFL_LLVM_LTO_STARTID: from which ID to start counting from for a " - "bb\n" "AFL_LLVM_LTO_DONTWRITEID: don't write the highest ID used to a " "global var\n" + "AFL_LLVM_LTO_STARTID: from which ID to start counting from for a " + "bb\n" "AFL_REAL_LD: use this lld linker instead of the compiled in path\n" "\nafl-clang-lto was built with linker target \"%s\" and LTO flags " "\"%s\"\n" diff --git a/src/afl-analyze.c b/src/afl-analyze.c index 3d86efb1..8a84b781 100644 --- a/src/afl-analyze.c +++ b/src/afl-analyze.c @@ -796,8 +796,10 @@ static void usage(u8 *argv0) { " (must contain abort_on_error=1 and symbolize=0)\n" "MSAN_OPTIONS: custom settings for MSAN\n" " (must contain exitcode="STRINGIFY(MSAN_ERROR)" and symbolize=0)\n" - "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" "AFL_ANALYZE_HEX: print file offsets in hexadecimal instead of decimal\n" + "AFL_MAP_SIZE: the shared memory size for that target. must be >= the size\n" + " the target was compiled for\n" + "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" "AFL_SKIP_BIN_CHECK: skip checking the location of and the target\n" , argv0, EXEC_TIMEOUT, MEM_LIMIT, doc_path); diff --git a/src/afl-fuzz.c b/src/afl-fuzz.c index 3cf57f86..2a1387a9 100644 --- a/src/afl-fuzz.c +++ b/src/afl-fuzz.c @@ -150,44 +150,46 @@ static void usage(afl_state_t *afl, u8 *argv0, int more_help) { if (more_help > 1) SAYF( "Environment variables used:\n" - "AFL_PATH: path to AFL support binaries\n" - "AFL_QUIET: suppress forkserver status messages\n" - "AFL_DEBUG_CHILD_OUTPUT: do not suppress stdout/stderr from target\n" "LD_BIND_LAZY: do not set LD_BIND_NOW env var for target\n" + "ASAN_OPTIONS: custom settings for ASAN\n" + " (must contain abort_on_error=1 and symbolize=0)\n" + "MSAN_OPTIONS: custom settings for MSAN\n" + " (must contain exitcode="STRINGIFY(MSAN_ERROR)" and symbolize=0)\n" + "AFL_AUTORESUME: resume fuzzing if directory specified by -o already exists\n" "AFL_BENCH_JUST_ONE: run the target just once\n" - "AFL_DUMB_FORKSRV: use fork server without feedback from target\n" + "AFL_BENCH_UNTIL_CRASH: exit soon when the first crashing input has been found\n" "AFL_CUSTOM_MUTATOR_LIBRARY: lib with afl_custom_fuzz() to mutate inputs\n" "AFL_CUSTOM_MUTATOR_ONLY: avoid AFL++'s internal mutators\n" - "AFL_PYTHON_MODULE: mutate and trim inputs with the specified Python module\n" "AFL_DEBUG: extra debugging output for Python mode trimming\n" + "AFL_DEBUG_CHILD_OUTPUT: do not suppress stdout/stderr from target\n" "AFL_DISABLE_TRIM: disable the trimming of test cases\n" - "AFL_NO_UI: switch status screen off\n" - "AFL_FORCE_UI: force showing the status screen (for virtual consoles)\n" - "AFL_NO_CPU_RED: avoid red color for showing very high cpu usage\n" - "AFL_SKIP_CPUFREQ: do not warn about variable cpu clocking\n" - "AFL_NO_SNAPSHOT: do not use the snapshot feature (if the snapshot lkm is loaded)\n" - "AFL_NO_FORKSRV: run target via execve instead of using the forkserver\n" - "AFL_NO_ARITH: skip arithmetic mutations in deterministic stage\n" - "AFL_SHUFFLE_QUEUE: reorder the input queue randomly on startup\n" + "AFL_DUMB_FORKSRV: use fork server without feedback from target\n" + "AFL_EXIT_WHEN_DONE: exit when all inputs are run and no new finds are found\n" "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_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" - "AFL_TMPDIR: directory to use for input file generation (ramdisk recommended)\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" + " the target was compiled for\n" "AFL_NO_AFFINITY: do not check for an unused cpu core to use for fuzzing\n" + "AFL_NO_ARITH: skip arithmetic mutations in deterministic stage\n" + "AFL_NO_CPU_RED: avoid red color for showing very high cpu usage\n" + "AFL_NO_FORKSRV: run target via execve instead of using the forkserver\n" + "AFL_NO_SNAPSHOT: do not use the snapshot feature (if the snapshot lkm is loaded)\n" + "AFL_NO_UI: switch status screen off\n" + "AFL_PATH: path to AFL support binaries\n" "AFL_POST_LIBRARY: postprocess generated test cases before use as target input\n" - "AFL_SKIP_CRASHES: during initial dry run do not terminate for crashing inputs\n" - "AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES: don't warn about core dump handlers\n" - "ASAN_OPTIONS: custom settings for ASAN\n" - " (must contain abort_on_error=1 and symbolize=0)\n" - "MSAN_OPTIONS: custom settings for MSAN\n" - " (must contain exitcode="STRINGIFY(MSAN_ERROR)" and symbolize=0)\n" + "AFL_PYTHON_MODULE: mutate and trim inputs with the specified Python module\n" + "AFL_QUIET: suppress forkserver status messages\n" + "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" + "AFL_SHUFFLE_QUEUE: reorder the input queue randomly on startup\n" "AFL_SKIP_BIN_CHECK: skip the check, if the target is an excutable\n" + "AFL_SKIP_CPUFREQ: do not warn about variable cpu clocking\n" + "AFL_SKIP_CRASHES: during initial dry run do not terminate for crashing inputs\n" + "AFL_TMPDIR: directory to use for input file generation (ramdisk recommended)\n" //"AFL_PERSISTENT: not supported anymore -> no effect, just a warning\n" //"AFL_DEFER_FORKSRV: not supported anymore -> no effect, just a warning\n" - "AFL_EXIT_WHEN_DONE: exit when all inputs are run and no new finds are found\n" - "AFL_BENCH_UNTIL_CRASH: exit soon when the first crashing input has been found\n" - "AFL_AUTORESUME: resume fuzzing if directory specified by -o already exists\n" "\n" ); else diff --git a/src/afl-showmap.c b/src/afl-showmap.c index c1561b4c..59c76d41 100644 --- a/src/afl-showmap.c +++ b/src/afl-showmap.c @@ -515,13 +515,16 @@ static void usage(u8 *argv0) { "For additional help, consult %s/README.md.\n\n" "Environment variables used:\n" - "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" - "AFL_DEBUG: enable extra developer output\n" - "AFL_QUIET: do not print extra informational output" + "LD_BIND_LAZY: do not set LD_BIND_NOW env var for target\n", "AFL_CMIN_CRASHES_ONLY: (cmin_mode) only write tuples for crashing " "inputs\n" "AFL_CMIN_ALLOW_ANY: (cmin_mode) write tuples for crashing inputs also\n" - "LD_BIND_LAZY: do not set LD_BIND_NOW env var for target\n", + "AFL_DEBUG: enable extra developer output\n" + "AFL_MAP_SIZE: the shared memory size for that target. must be >= the " + "size\n" + " the target was compiled for\n" + "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" + "AFL_QUIET: do not print extra informational output" argv0, MEM_LIMIT, doc_path); exit(1); diff --git a/src/afl-tmin.c b/src/afl-tmin.c index e366d260..ad7d70c7 100644 --- a/src/afl-tmin.c +++ b/src/afl-tmin.c @@ -741,7 +741,9 @@ static void usage(u8 *argv0) { " (must contain abort_on_error=1 and symbolize=0)\n" "MSAN_OPTIONS: custom settings for MSAN\n" " (must contain exitcode="STRINGIFY(MSAN_ERROR)" and symbolize=0)\n" - "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" + "AFL_MAP_SIZE: the shared memory size for that target. must be >= the size\n" + " the target was compiled for\n" + "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" "AFL_TMIN_EXACT: require execution paths to match for crashing inputs\n" , argv0, EXEC_TIMEOUT, MEM_LIMIT, doc_path); -- cgit 1.4.1 From 2162fd8e1a1ceb745c1fcf87fb6a1053508591c4 Mon Sep 17 00:00:00 2001 From: van Hauser Date: Fri, 17 Apr 2020 10:46:35 +0200 Subject: preliminary stuff for AFL_MAP_SIZE and afl-llvm-pass --- llvm_mode/afl-llvm-lto-instrumentation.so.cc | 2 +- llvm_mode/afl-llvm-pass.so.cc | 68 +++++++++++++++++++++++++++- src/afl-showmap.c | 4 +- 3 files changed, 69 insertions(+), 5 deletions(-) (limited to 'llvm_mode') diff --git a/llvm_mode/afl-llvm-lto-instrumentation.so.cc b/llvm_mode/afl-llvm-lto-instrumentation.so.cc index a5058974..ece3201f 100644 --- a/llvm_mode/afl-llvm-lto-instrumentation.so.cc +++ b/llvm_mode/afl-llvm-lto-instrumentation.so.cc @@ -637,7 +637,7 @@ bool AFLLTOPass::runOnModule(Module &M) { if (!f) { fprintf(stderr, - "Error: init function could not be found (this hould not " + "Error: init function could not be found (this should not " "happen)\n"); exit(-1); diff --git a/llvm_mode/afl-llvm-pass.so.cc b/llvm_mode/afl-llvm-pass.so.cc index b4249802..71abcd05 100644 --- a/llvm_mode/afl-llvm-pass.so.cc +++ b/llvm_mode/afl-llvm-pass.so.cc @@ -125,6 +125,7 @@ class AFLCoverage : public ModulePass { std::list myWhitelist; uint32_t ngram_size = 0; uint32_t debug = 0; + uint32_t map_size = MAP_SIZE; char * ctx_str = NULL; }; @@ -192,6 +193,19 @@ bool AFLCoverage::runOnModule(Module &M) { be_quiet = 1; + /* + char *ptr; + if ((ptr = getenv("AFL_MAP_SIZE")) || (ptr = getenv("AFL_MAPSIZE"))) { + + map_size = atoi(ptr); + if (map_size < 8 || map_size > (1 << 29)) + FATAL("illegal AFL_MAP_SIZE %u, must be between 2^3 and 2^30", + map_size); if (map_size % 8) map_size = (((map_size >> 3) + 1) << 3); + + } + + */ + /* Decide instrumentation ratio */ char * inst_ratio_str = getenv("AFL_INST_RATIO"); @@ -365,7 +379,7 @@ bool AFLCoverage::runOnModule(Module &M) { // if yes we store a context ID for this function in the global var if (has_calls) { - ConstantInt *NewCtx = ConstantInt::get(Int32Ty, AFL_R(MAP_SIZE)); + ConstantInt *NewCtx = ConstantInt::get(Int32Ty, AFL_R(map_size)); StoreInst * StoreCtx = IRB.CreateStore(NewCtx, AFLContext); StoreCtx->setMetadata(M.getMDKindID("nosanitize"), MDNode::get(C, None)); @@ -509,7 +523,7 @@ bool AFLCoverage::runOnModule(Module &M) { /* Make up cur_loc */ // cur_loc++; - cur_loc = AFL_R(MAP_SIZE); + cur_loc = AFL_R(map_size); /* There is a problem with Ubuntu 18.04 and llvm 6.0 (see issue #63). The inline function successors() is not inlined and also not found at runtime @@ -705,6 +719,56 @@ bool AFLCoverage::runOnModule(Module &M) { } + /* + // This is currently disabled because we not only need to create/insert a + // function (easy), but also add it as a constructor with an ID < 5 + + if (getenv("AFL_LLVM_DONTWRITEID") == NULL) { + + // yes we could create our own function, insert it into ctors ... + // but this would be a pain in the butt ... so we use afl-llvm-rt.o + + Function *f = ... + + if (!f) { + + fprintf(stderr, + "Error: init function could not be created (this should not + happen)\n"); exit(-1); + + } + + ... constructor for f = 4 + + BasicBlock *bb = &f->getEntryBlock(); + if (!bb) { + + fprintf(stderr, + "Error: init function does not have an EntryBlock (this should + not happen)\n"); exit(-1); + + } + + BasicBlock::iterator IP = bb->getFirstInsertionPt(); + IRBuilder<> IRB(&(*IP)); + + if (map_size <= 0x800000) { + + GlobalVariable *AFLFinalLoc = new GlobalVariable( + M, Int32Ty, true, GlobalValue::ExternalLinkage, 0, + "__afl_final_loc", 0, GlobalVariable::GeneralDynamicTLSModel, 0, + false); + ConstantInt *const_loc = ConstantInt::get(Int32Ty, map_size); + StoreInst * StoreFinalLoc = IRB.CreateStore(const_loc, AFLFinalLoc); + StoreFinalLoc->setMetadata(M.getMDKindID("nosanitize"), + MDNode::get(C, None)); + + } + + } + + */ + /* Say something nice. */ if (!be_quiet) { diff --git a/src/afl-showmap.c b/src/afl-showmap.c index 59c76d41..a11c128a 100644 --- a/src/afl-showmap.c +++ b/src/afl-showmap.c @@ -524,8 +524,8 @@ static void usage(u8 *argv0) { "size\n" " the target was compiled for\n" "AFL_PRELOAD: LD_PRELOAD / DYLD_INSERT_LIBRARIES settings for target\n" - "AFL_QUIET: do not print extra informational output" - argv0, MEM_LIMIT, doc_path); + "AFL_QUIET: do not print extra informational output" argv0, + MEM_LIMIT, doc_path); exit(1); -- cgit 1.4.1