diff options
| -rw-r--r-- | README.md | 2 | ||||
| -rw-r--r-- | docs/Changelog.md | 1 | ||||
| -rw-r--r-- | docs/env_variables.md | 4 | ||||
| -rw-r--r-- | docs/notes_for_asan.md | 2 | ||||
| -rw-r--r-- | llvm_mode/LLVMInsTrim.so.cc | 1 | ||||
| -rw-r--r-- | llvm_mode/afl-clang-fast.c | 21 | ||||
| -rw-r--r-- | llvm_mode/afl-llvm-lto-instrumentation.so.cc | 1 | ||||
| -rw-r--r-- | llvm_mode/afl-llvm-pass.so.cc | 1 | ||||
| -rw-r--r-- | src/afl-common.c | 2 |
9 files changed, 29 insertions, 6 deletions
diff --git a/README.md b/README.md index 781c8b49..827a7aec 100644 --- a/README.md +++ b/README.md @@ -259,7 +259,7 @@ superior to blind fuzzing or coverage-only tools. ## Instrumenting programs for use with AFL PLEASE NOTE: llvm_mode compilation with afl-clang-fast/afl-clang-fast++ -instead of afl-gcc/afl-g++ is much faster and has a few cool features. +instead of afl-gcc/afl-g++ is much faster and has many cool features. See llvm_mode/ - however few code does not compile with llvm. We support llvm versions 3.8.0 to 11. diff --git a/docs/Changelog.md b/docs/Changelog.md index 6af269ce..198909d1 100644 --- a/docs/Changelog.md +++ b/docs/Changelog.md @@ -31,6 +31,7 @@ sending a mail to <afl-users+subscribe@googlegroups.com>. the last 5 queue entries - rare: puts focus on queue entries that hits rare branches, also ignores runtime + - llvm_mode: added Control Flow Integrity sanatizer (AFL_USE_CFISAN) - LTO collision free instrumented added in llvm_mode with afl-clang-lto - note that this mode is amazing, but quite some targets won't compile - Added llvm_mode NGRAM prev_loc coverage by Adrean Herrera diff --git a/docs/env_variables.md b/docs/env_variables.md index 98f27bdf..ae283b1c 100644 --- a/docs/env_variables.md +++ b/docs/env_variables.md @@ -31,7 +31,9 @@ tools make fairly broad use of environmental variables: (You can also enable MSAN via AFL_USE_MSAN; ASAN and MSAN come with the same gotchas; the modes are mutually exclusive. UBSAN can be enabled - similarly by setting the environment variable AFL_USE_UBSAN=1) + similarly by setting the environment variable AFL_USE_UBSAN=1. Finally + there is the Control Flow Integrity sanitizer that can be activated by + AFL_USE_CFISAN=1) - Setting AFL_CC, AFL_CXX, and AFL_AS lets you use alternate downstream compilation tools, rather than the default 'clang', 'gcc', or 'as' binaries diff --git a/docs/notes_for_asan.md b/docs/notes_for_asan.md index b65873be..6a4806c0 100644 --- a/docs/notes_for_asan.md +++ b/docs/notes_for_asan.md @@ -29,7 +29,7 @@ Note that ASAN is incompatible with -static, so be mindful of that. (You can also use AFL_USE_MSAN=1 to enable MSAN instead.) NOTE: if you run several slaves only one should run the target compiled with -ASAN (and UBSAN), the others should run the target with no sanitizers +ASAN (and UBSAN, CFISAN), the others should run the target with no sanitizers compiled in. There is also the option of generating a corpus using a non-ASAN binary, and diff --git a/llvm_mode/LLVMInsTrim.so.cc b/llvm_mode/LLVMInsTrim.so.cc index a94eb907..c4033523 100644 --- a/llvm_mode/LLVMInsTrim.so.cc +++ b/llvm_mode/LLVMInsTrim.so.cc @@ -513,6 +513,7 @@ struct InsTrim : public ModulePass { getenv("AFL_HARDEN") ? "hardened" : "non-hardened", getenv("AFL_USE_ASAN") ? ", ASAN" : "", getenv("AFL_USE_MSAN") ? ", MSAN" : "", + getenv("AFL_USE_CFISAN") ? ", CFISAN" : "", getenv("AFL_USE_UBSAN") ? ", UBSAN" : ""); OKF("Instrumented %u locations (%llu, %llu) (%s mode)\n", total_instr, diff --git a/llvm_mode/afl-clang-fast.c b/llvm_mode/afl-clang-fast.c index 7050e22d..c45c8799 100644 --- a/llvm_mode/afl-clang-fast.c +++ b/llvm_mode/afl-clang-fast.c @@ -135,7 +135,7 @@ static void find_obj(u8 *argv0) { /* Copy argv to cc_params, making the necessary edits. */ -static void edit_params(u32 argc, char **argv) { +static void edit_params(u32 argc, char **argv, char **envp) { u8 fortify_set = 0, asan_set = 0, x_set = 0, maybe_linking = 1, bit_mode = 0; u8 has_llvm_config = 0; @@ -395,6 +395,22 @@ static void edit_params(u32 argc, char **argv) { } + if (getenv("AFL_USE_CFISAN")) { + + if (!lto_mode) { + + uint32_t i = 0, found = 0; + while (envp[i] != NULL && !found) + if (strncmp("-flto", envp[i++], 5) == 0) + found = 1; + if (!found) cc_params[cc_par_cnt++] = "-flto"; + + } + cc_params[cc_par_cnt++] = "-fsanitize=cfi"; + cc_params[cc_par_cnt++] = "-fvisibility=hidden"; + + } + #ifdef USE_TRACE_PC if (getenv("USE_TRACE_PC") || getenv("AFL_USE_TRACE_PC") || @@ -596,6 +612,7 @@ int main(int argc, char **argv, char **envp) { "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_LLVM_NOT_ZERO: use cycling trace counters that skip zero\n" @@ -685,7 +702,7 @@ int main(int argc, char **argv, char **envp) { find_obj(argv[0]); #endif - edit_params(argc, argv); + edit_params(argc, argv, envp); if (debug) { diff --git a/llvm_mode/afl-llvm-lto-instrumentation.so.cc b/llvm_mode/afl-llvm-lto-instrumentation.so.cc index febb8950..8bf485af 100644 --- a/llvm_mode/afl-llvm-lto-instrumentation.so.cc +++ b/llvm_mode/afl-llvm-lto-instrumentation.so.cc @@ -396,6 +396,7 @@ bool AFLLTOPass::runOnModule(Module &M) { getenv("AFL_HARDEN") ? "hardened" : "non-hardened", getenv("AFL_USE_ASAN") ? ", ASAN" : "", getenv("AFL_USE_MSAN") ? ", MSAN" : "", + getenv("AFL_USE_CFISAN") ? ", CFISAN" : "", getenv("AFL_USE_UBSAN") ? ", UBSAN" : ""); OKF("Instrumented %u locations with no collisions (on average %llu " "collisions would be in afl-gcc/afl-clang-fast) (%s mode).", diff --git a/llvm_mode/afl-llvm-pass.so.cc b/llvm_mode/afl-llvm-pass.so.cc index fefd9edd..e8f449b1 100644 --- a/llvm_mode/afl-llvm-pass.so.cc +++ b/llvm_mode/afl-llvm-pass.so.cc @@ -572,6 +572,7 @@ bool AFLCoverage::runOnModule(Module &M) { getenv("AFL_HARDEN") ? "hardened" : "non-hardened", getenv("AFL_USE_ASAN") ? ", ASAN" : "", getenv("AFL_USE_MSAN") ? ", MSAN" : "", + getenv("AFL_USE_CFISAN") ? ", CFISAN" : "", getenv("AFL_USE_UBSAN") ? ", UBSAN" : ""); OKF("Instrumented %u locations (%s mode, ratio %u%%).", inst_blocks, modeline, inst_ratio); diff --git a/src/afl-common.c b/src/afl-common.c index 8c4d53e8..e10de6b3 100644 --- a/src/afl-common.c +++ b/src/afl-common.c @@ -73,7 +73,7 @@ char * afl_environment_variables[] = { "AFL_SHUFFLE_QUEUE", "AFL_SKIP_BIN_CHECK", "AFL_SKIP_CPUFREQ", "AFL_SKIP_CRASHES", "AFL_TMIN_EXACT", "AFL_TMPDIR", "AFL_TOKEN_FILE", "AFL_TRACE_PC", "AFL_USE_ASAN", "AFL_USE_MSAN", "AFL_USE_TRACE_PC", - "AFL_USE_UBSAN", "AFL_WINE_PATH", NULL}; + "AFL_USE_UBSAN", "AFL_USE_CFISAN", "AFL_WINE_PATH", NULL}; void detect_file_args(char **argv, u8 *prog_in, u8 *use_stdin) { |