diff options
| -rw-r--r-- | docs/env_variables.md | 5 | ||||
| -rw-r--r-- | include/envs.h | 6 | ||||
| -rw-r--r-- | instrumentation/README.gcc_plugin.md | 5 | ||||
| -rw-r--r-- | instrumentation/afl-gcc-cmplog-pass.so.cc | 3 | ||||
| -rw-r--r-- | instrumentation/afl-gcc-cmptrs-pass.so.cc | 3 | ||||
| -rw-r--r-- | instrumentation/afl-gcc-pass.so.cc | 3 | ||||
| -rw-r--r-- | src/afl-cc.c | 2 |
7 files changed, 20 insertions, 7 deletions
diff --git a/docs/env_variables.md b/docs/env_variables.md index d0789105..d1edb6fd 100644 --- a/docs/env_variables.md +++ b/docs/env_variables.md @@ -326,6 +326,11 @@ mode. [instrumentation/README.instrument_list.md](../instrumentation/README.instrument_list.md) for more information. + Setting `AFL_GCC_DISABLE_VERSION_CHECK=1` will disable the GCC plugin + version check if the target GCC plugin differs from the system-installed + version, resolving issues caused by version mismatches between GCC and + the plugin. + Setting `AFL_GCC_OUT_OF_LINE=1` will instruct afl-gcc-fast to instrument the code with calls to an injected subroutine instead of the much more efficient inline instrumentation. diff --git a/include/envs.h b/include/envs.h index 202de752..cca9baa8 100644 --- a/include/envs.h +++ b/include/envs.h @@ -52,9 +52,9 @@ static char *afl_environment_variables[] = { "AFL_FRIDA_VERBOSE", "AFL_OLD_FORKSERVER", "AFL_OPT_LEVEL", "AFL_FUZZER_ARGS", // oss-fuzz "AFL_FUZZER_STATS_UPDATE_INTERVAL", "AFL_GDB", "AFL_GCC_ALLOWLIST", - "AFL_GCC_DENYLIST", "AFL_GCC_BLOCKLIST", "AFL_GCC_INSTRUMENT_FILE", - "AFL_GCC_OUT_OF_LINE", "AFL_GCC_SKIP_NEVERZERO", "AFL_GCJ", - "AFL_HANG_TMOUT", "AFL_FORKSRV_INIT_TMOUT", "AFL_HARDEN", + "AFL_GCC_DENYLIST", "AFL_GCC_BLOCKLIST", "AFL_GCC_DISABLE_VERSION_CHECK", + "AFL_GCC_INSTRUMENT_FILE", "AFL_GCC_OUT_OF_LINE", "AFL_GCC_SKIP_NEVERZERO", + "AFL_GCJ", "AFL_HANG_TMOUT", "AFL_FORKSRV_INIT_TMOUT", "AFL_HARDEN", "AFL_I_DONT_CARE_ABOUT_MISSING_CRASHES", "AFL_IGNORE_PROBLEMS", "AFL_IGNORE_PROBLEMS_COVERAGE", "AFL_IGNORE_SEED_PROBLEMS", "AFL_IGNORE_TIMEOUTS", "AFL_IGNORE_UNKNOWN_ENVS", "AFL_IMPORT_FIRST", diff --git a/instrumentation/README.gcc_plugin.md b/instrumentation/README.gcc_plugin.md index 011a574a..34004dc7 100644 --- a/instrumentation/README.gcc_plugin.md +++ b/instrumentation/README.gcc_plugin.md @@ -51,7 +51,10 @@ The idea and much of the implementation comes from Laszlo Szekeres. In order to leverage this mechanism, you need to have modern enough GCC (>= version 4.5.0) and the plugin development headers installed on your system. That should be all you need. On Debian machines, these headers can be acquired by -installing the `gcc-VERSION-plugin-dev` packages. +installing the `gcc-VERSION-plugin-dev` packages. If you're compiling a GCC +plugin that differs from the system-installed version and encounter issues +with version checks, you can use the `AFL_GCC_DISABLE_VERSION_CHECK` environment +variable. To build the instrumentation itself, type `make`. This will generate binaries called `afl-gcc-fast` and `afl-g++-fast` in the parent directory. diff --git a/instrumentation/afl-gcc-cmplog-pass.so.cc b/instrumentation/afl-gcc-cmplog-pass.so.cc index 774dd5fd..38fce961 100644 --- a/instrumentation/afl-gcc-cmplog-pass.so.cc +++ b/instrumentation/afl-gcc-cmplog-pass.so.cc @@ -370,7 +370,8 @@ Set AFL_QUIET in the environment to silence it.\n\ int plugin_init(struct plugin_name_args *info, struct plugin_gcc_version *version) { - if (!plugin_default_version_check(version, &gcc_version)) + if (!plugin_default_version_check(version, &gcc_version) && + !getenv("AFL_GCC_DISABLE_VERSION_CHECK")) FATAL(G_("GCC and plugin have incompatible versions, expected GCC %s, " "is %s"), gcc_version.basever, version->basever); diff --git a/instrumentation/afl-gcc-cmptrs-pass.so.cc b/instrumentation/afl-gcc-cmptrs-pass.so.cc index 96bd5ba8..360b035a 100644 --- a/instrumentation/afl-gcc-cmptrs-pass.so.cc +++ b/instrumentation/afl-gcc-cmptrs-pass.so.cc @@ -338,7 +338,8 @@ Set AFL_QUIET in the environment to silence it.\n\ int plugin_init(struct plugin_name_args *info, struct plugin_gcc_version *version) { - if (!plugin_default_version_check(version, &gcc_version)) + if (!plugin_default_version_check(version, &gcc_version) && + !getenv("AFL_GCC_DISABLE_VERSION_CHECK")) FATAL(G_("GCC and plugin have incompatible versions, expected GCC %s, " "is %s"), gcc_version.basever, version->basever); diff --git a/instrumentation/afl-gcc-pass.so.cc b/instrumentation/afl-gcc-pass.so.cc index 41b1e5af..26f7bd19 100644 --- a/instrumentation/afl-gcc-pass.so.cc +++ b/instrumentation/afl-gcc-pass.so.cc @@ -478,7 +478,8 @@ Specify -frandom-seed for reproducible instrumentation.\n\ int plugin_init(struct plugin_name_args *info, struct plugin_gcc_version *version) { - if (!plugin_default_version_check(version, &gcc_version)) + if (!plugin_default_version_check(version, &gcc_version) && + !getenv("AFL_GCC_DISABLE_VERSION_CHECK")) FATAL(G_("GCC and plugin have incompatible versions, expected GCC %s, " "is %s"), gcc_version.basever, version->basever); diff --git a/src/afl-cc.c b/src/afl-cc.c index 677a6b2f..6f634b53 100644 --- a/src/afl-cc.c +++ b/src/afl-cc.c @@ -2958,6 +2958,8 @@ static void maybe_usage(aflcc_state_t *aflcc, int argc, char **argv) { SAYF( "\nGCC Plugin-specific environment variables:\n" " AFL_GCC_CMPLOG: log operands of comparisons (RedQueen mutator)\n" + " AFL_GCC_DISABLE_VERSION_CHECK: disable GCC plugin version " + "control\n" " AFL_GCC_OUT_OF_LINE: disable inlined instrumentation\n" " AFL_GCC_SKIP_NEVERZERO: do not skip zero on trace counters\n" " AFL_GCC_INSTRUMENT_FILE: enable selective instrumentation by " |