sanitizers.c - platform/external/honggfuzz - Git at Google

 #include "sanitizers.h"

 #include <ctype.h>
 #include <dirent.h>
 #include <inttypes.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>

 #include "libcommon/common.h"
 #include "libcommon/files.h"
 #include "libcommon/log.h"
 #include "libcommon/util.h"

 /* Stringify */
 #define XSTR(x) #x
 #define STR(x) XSTR(x)

 /*
  * All clang sanitizers, except ASan, can be activated for target binaries
  * with or without the matching runtime library (libcompiler_rt). If runtime
  * libraries are included in target fuzzing environment, we can benefit from the
  * various Die() callbacks and abort/exit logic manipulation. However, some
  * setups (e.g. Android production ARM/ARM64 devices) enable sanitizers, such as
  * UBSan, without the runtime libraries. As such, their default ftrap is activated
  * which is for most cases a SIGABRT. For these cases end-user needs to enable
  * SIGABRT monitoring flag, otherwise these crashes will be missed.
  *
  * Normally SIGABRT is not a wanted signal to monitor for Android, since it produces
  * lots of useless crashes due to way Android process termination hacks work. As
  * a result the sanitizer's 'abort_on_error' flag cannot be utilized since it
  * invokes abort() internally. In order to not lose crashes a custom exitcode can
  * be registered and monitored. Since exitcode is a global flag, it's assumed
  * that target is compiled with only one sanitizer type enabled at a time.
  *
  * For cases where clang runtime library linking is not an option, SIGABRT should
  * be monitored even for noisy targets, such as the Android OS, since no viable
  * alternative exists.
  *
  * There might be cases where ASan instrumented targets crash while generating
  * reports for detected errors (inside __asan_report_error() proc). Under such
  * scenarios target fails to exit or SIGABRT (AsanDie() proc) as defined in
  * ASAN_OPTIONS flags, leaving garbage logs. An attempt is made to parse such
  * logs for cases where enough data are written to identify potentially missed
  * crashes. If ASan internal error results into a SIGSEGV being raised, it
  * will get caught from ptrace API, handling the discovered ASan internal crash.
  */

 /* 'log_path' output directory for sanitizer reports */
 #define kSANLOGDIR "log_path="

 /* 'coverage_dir' output directory for coverage data files is set dynamically */
 #define kSANCOVDIR "coverage_dir="

 /* Raise SIGABRT on error or continue with exitcode logic */
 #define kABORT_ENABLED "abort_on_error=1"
 #define kABORT_DISABLED "abort_on_error=0"

 /*
  * Common sanitizer flags
  *
  * symbolize: Disable symbolication since it changes logs (which are parsed) format
  */
 #define kSAN_COMMON "symbolize=0"

 /* --{ ASan }-- */
 /*
  *Sanitizer specific flags (notice that if enabled 'abort_on_error' has priority
  * over exitcode')
  */
 #define kASAN_COMMON_OPTS        \
     "allow_user_segv_handler=1:" \
     "handle_segv=0:"             \
     "allocator_may_return_null=1:" kSAN_COMMON ":exitcode=" STR(HF_SAN_EXIT_CODE)
 /* Platform specific flags */
 #if defined(__ANDROID__)
 /*
  * start_deactivated: Enable on Android to reduce memory usage (useful when not all
  *                    target's DSOs are compiled with sanitizer enabled
  */
 #define kASAN_OPTS kASAN_COMMON_OPTS ":start_deactivated=1"
 #else
 #define kASAN_OPTS kASAN_COMMON_OPTS
 #endif

 /* --{ UBSan }-- */
 #define kUBSAN_OPTS kSAN_COMMON ":exitcode=" STR(HF_SAN_EXIT_CODE)

 /* --{ MSan }-- */
 #define kMSAN_OPTS \
     kSAN_COMMON ":exit_code=" STR(HF_SAN_EXIT_CODE) ":"                                            \
                                                     "wrap_signals=0:print_stats=1"

 /* If no sanitzer support was requested, simply make it use abort() on errors */
 #define kSAN_REGULAR                                                 \
     "abort_on_error=1:handle_segv=0:handle_sigbus=0:handle_abort=0:" \
     "handle_sigill=0:handle_sigfpe=0:allocator_may_return_null=1:"   \
     "symbolize=1:detect_leaks=0:disable_coredump=0:log_path=stderr"

 /*
  * If the program ends with a signal that ASan does not handle (or can not
  * handle at all, like SIGKILL), coverage data will be lost. This is a big
  * problem on Android, where SIGKILL is a normal way of evicting applications
  * from memory. With 'coverage_direct=1' coverage data is written to a
  * memory-mapped file as soon as it collected. Non-Android targets can disable
  * coverage direct when more coverage data collection methods are implemented.
  */
 #define kSAN_COV_OPTS "coverage=1:coverage_direct=1"

 static bool sanitizers_Regular(void) {
     if (setenv("ASAN_OPTIONS", kSAN_REGULAR, 1) == -1) {
         PLOG_E("setenv(ASAN_OPTIONS=%s", kSAN_REGULAR);
         return false;
     }
     if (setenv("MSAN_OPTIONS", kSAN_REGULAR, 1) == -1) {
         PLOG_E("setenv(MSAN_OPTIONS=%s", kSAN_REGULAR);
         return false;
     }
     if (setenv("UBSAN_OPTIONS", kSAN_REGULAR, 1) == -1) {
         PLOG_E("setenv(UBSAN_OPTIONS=%s", kSAN_REGULAR);
         return false;
     }
     return true;
 }

 bool sanitizers_Init(honggfuzz_t* hfuzz) {
     if (hfuzz->linux.pid > 0) {
         return true;
     }

     if (hfuzz->enableSanitizers == false) {
         return sanitizers_Regular();
     }

     /* Set sanitizer flags once to avoid performance overhead per worker spawn */
     size_t flagsSz = 0;

     /* Larger constant combination + 2 dynamic paths */
     size_t bufSz = sizeof(kASAN_OPTS) + 1 + sizeof(kABORT_ENABLED) + 1 + sizeof(kSANLOGDIR) +
                    PATH_MAX + 1 + sizeof(kSANCOVDIR) + PATH_MAX + 1;
     char* san_opts = util_Calloc(bufSz);
     defer { free(san_opts); };

     char* abortFlag;
     if (hfuzz->monitorSIGABRT) {
         abortFlag = kABORT_ENABLED;
     } else {
         abortFlag = kABORT_DISABLED;
     }

     /* Address Sanitizer (ASan) */
     if (hfuzz->useSanCov) {
         snprintf(san_opts, bufSz, "%s:%s:%s:%s%s/%s:%s%s/%s", kASAN_OPTS, abortFlag, kSAN_COV_OPTS,
             kSANCOVDIR, hfuzz->io.workDir, _HF_SANCOV_DIR, kSANLOGDIR, hfuzz->io.workDir,
             kLOGPREFIX);
     } else {
         snprintf(san_opts, bufSz, "%s:%s:%s%s/%s", kASAN_OPTS, abortFlag, kSANLOGDIR,
             hfuzz->io.workDir, kLOGPREFIX);
     }

     flagsSz = strlen(san_opts) + 1;
     hfuzz->sanOpts.asanOpts = util_Calloc(flagsSz);
     memcpy(hfuzz->sanOpts.asanOpts, san_opts, flagsSz);
     LOG_D("ASAN_OPTIONS=%s", hfuzz->sanOpts.asanOpts);

     /* Undefined Behavior Sanitizer (UBSan) */
     memset(san_opts, 0, bufSz);
     if (hfuzz->useSanCov) {
         snprintf(san_opts, bufSz, "%s:%s:%s:%s%s/%s:%s%s/%s", kUBSAN_OPTS, abortFlag, kSAN_COV_OPTS,
             kSANCOVDIR, hfuzz->io.workDir, _HF_SANCOV_DIR, kSANLOGDIR, hfuzz->io.workDir,
             kLOGPREFIX);
     } else {
         snprintf(san_opts, bufSz, "%s:%s:%s%s/%s", kUBSAN_OPTS, abortFlag, kSANLOGDIR,
             hfuzz->io.workDir, kLOGPREFIX);
     }

     flagsSz = strlen(san_opts) + 1;
     hfuzz->sanOpts.ubsanOpts = util_Calloc(flagsSz);
     memcpy(hfuzz->sanOpts.ubsanOpts, san_opts, flagsSz);
     LOG_D("UBSAN_OPTIONS=%s", hfuzz->sanOpts.ubsanOpts);

     /* Memory Sanitizer (MSan) */
     memset(san_opts, 0, bufSz);

     if (hfuzz->useSanCov) {
         snprintf(san_opts, bufSz, "%s:%s:%s:%s%s/%s:%s%s/%s", kMSAN_OPTS, abortFlag, kSAN_COV_OPTS,
             kSANCOVDIR, hfuzz->io.workDir, _HF_SANCOV_DIR, kSANLOGDIR, hfuzz->io.workDir,
             kLOGPREFIX);
     } else {
         snprintf(san_opts, bufSz, "%s:%s:%s%s/%s", kMSAN_OPTS, abortFlag, kSANLOGDIR,
             hfuzz->io.workDir, kLOGPREFIX);
     }

     flagsSz = strlen(san_opts) + 1;
     hfuzz->sanOpts.msanOpts = util_Calloc(flagsSz);
     memcpy(hfuzz->sanOpts.msanOpts, san_opts, flagsSz);
     LOG_D("MSAN_OPTIONS=%s", hfuzz->sanOpts.msanOpts);

     return true;
 }

 bool sanitizers_prepareExecve(run_t* run) {
     /* Address Sanitizer (ASan) */
     if (run->global->sanOpts.asanOpts) {
         if (setenv("ASAN_OPTIONS", run->global->sanOpts.asanOpts, 1) == -1) {
             PLOG_E("setenv(ASAN_OPTIONS) failed");
             return false;
         }
     }

     /* Memory Sanitizer (MSan) */
     if (run->global->sanOpts.msanOpts) {
         if (setenv("MSAN_OPTIONS", run->global->sanOpts.msanOpts, 1) == -1) {
             PLOG_E("setenv(MSAN_OPTIONS) failed");
             return false;
         }
     }

     /* Undefined Behavior Sanitizer (UBSan) */
     if (run->global->sanOpts.ubsanOpts) {
         if (setenv("UBSAN_OPTIONS", run->global->sanOpts.ubsanOpts, 1) == -1) {
             PLOG_E("setenv(UBSAN_OPTIONS) failed");
             return false;
         }
     }

     return true;
 }
	#include "sanitizers.h"

	#include <ctype.h>
	#include <dirent.h>
	#include <inttypes.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/mman.h>
	#include <sys/stat.h>
	#include <sys/types.h>

	#include "libcommon/common.h"
	#include "libcommon/files.h"
	#include "libcommon/log.h"
	#include "libcommon/util.h"

	/* Stringify */
	#define XSTR(x) #x
	#define STR(x) XSTR(x)

	/*
	* All clang sanitizers, except ASan, can be activated for target binaries
	* with or without the matching runtime library (libcompiler_rt). If runtime
	* libraries are included in target fuzzing environment, we can benefit from the
	* various Die() callbacks and abort/exit logic manipulation. However, some
	* setups (e.g. Android production ARM/ARM64 devices) enable sanitizers, such as
	* UBSan, without the runtime libraries. As such, their default ftrap is activated
	* which is for most cases a SIGABRT. For these cases end-user needs to enable
	* SIGABRT monitoring flag, otherwise these crashes will be missed.
	*
	* Normally SIGABRT is not a wanted signal to monitor for Android, since it produces
	* lots of useless crashes due to way Android process termination hacks work. As
	* a result the sanitizer's 'abort_on_error' flag cannot be utilized since it
	* invokes abort() internally. In order to not lose crashes a custom exitcode can
	* be registered and monitored. Since exitcode is a global flag, it's assumed
	* that target is compiled with only one sanitizer type enabled at a time.
	*
	* For cases where clang runtime library linking is not an option, SIGABRT should
	* be monitored even for noisy targets, such as the Android OS, since no viable
	* alternative exists.
	*
	* There might be cases where ASan instrumented targets crash while generating
	* reports for detected errors (inside __asan_report_error() proc). Under such
	* scenarios target fails to exit or SIGABRT (AsanDie() proc) as defined in
	* ASAN_OPTIONS flags, leaving garbage logs. An attempt is made to parse such
	* logs for cases where enough data are written to identify potentially missed
	* crashes. If ASan internal error results into a SIGSEGV being raised, it
	* will get caught from ptrace API, handling the discovered ASan internal crash.
	*/

	/* 'log_path' output directory for sanitizer reports */
	#define kSANLOGDIR "log_path="

	/* 'coverage_dir' output directory for coverage data files is set dynamically */
	#define kSANCOVDIR "coverage_dir="

	/* Raise SIGABRT on error or continue with exitcode logic */
	#define kABORT_ENABLED "abort_on_error=1"
	#define kABORT_DISABLED "abort_on_error=0"

	/*
	* Common sanitizer flags
	*
	* symbolize: Disable symbolication since it changes logs (which are parsed) format
	*/
	#define kSAN_COMMON "symbolize=0"

	/* --{ ASan }-- */
	/*
	*Sanitizer specific flags (notice that if enabled 'abort_on_error' has priority
	* over exitcode')
	*/
	#define kASAN_COMMON_OPTS \
	"allow_user_segv_handler=1:" \
	"handle_segv=0:" \
	"allocator_may_return_null=1:" kSAN_COMMON ":exitcode=" STR(HF_SAN_EXIT_CODE)
	/* Platform specific flags */
	#if defined(__ANDROID__)
	/*
	* start_deactivated: Enable on Android to reduce memory usage (useful when not all
	* target's DSOs are compiled with sanitizer enabled
	*/
	#define kASAN_OPTS kASAN_COMMON_OPTS ":start_deactivated=1"
	#else
	#define kASAN_OPTS kASAN_COMMON_OPTS
	#endif

	/* --{ UBSan }-- */
	#define kUBSAN_OPTS kSAN_COMMON ":exitcode=" STR(HF_SAN_EXIT_CODE)

	/* --{ MSan }-- */
	#define kMSAN_OPTS \
	kSAN_COMMON ":exit_code=" STR(HF_SAN_EXIT_CODE) ":" \
	"wrap_signals=0:print_stats=1"

	/* If no sanitzer support was requested, simply make it use abort() on errors */
	#define kSAN_REGULAR \
	"abort_on_error=1:handle_segv=0:handle_sigbus=0:handle_abort=0:" \
	"handle_sigill=0:handle_sigfpe=0:allocator_may_return_null=1:" \
	"symbolize=1:detect_leaks=0:disable_coredump=0:log_path=stderr"

	/*
	* If the program ends with a signal that ASan does not handle (or can not
	* handle at all, like SIGKILL), coverage data will be lost. This is a big
	* problem on Android, where SIGKILL is a normal way of evicting applications
	* from memory. With 'coverage_direct=1' coverage data is written to a
	* memory-mapped file as soon as it collected. Non-Android targets can disable
	* coverage direct when more coverage data collection methods are implemented.
	*/
	#define kSAN_COV_OPTS "coverage=1:coverage_direct=1"

	static bool sanitizers_Regular(void) {
	if (setenv("ASAN_OPTIONS", kSAN_REGULAR, 1) == -1) {
	PLOG_E("setenv(ASAN_OPTIONS=%s", kSAN_REGULAR);
	return false;
	}
	if (setenv("MSAN_OPTIONS", kSAN_REGULAR, 1) == -1) {
	PLOG_E("setenv(MSAN_OPTIONS=%s", kSAN_REGULAR);
	return false;
	}
	if (setenv("UBSAN_OPTIONS", kSAN_REGULAR, 1) == -1) {
	PLOG_E("setenv(UBSAN_OPTIONS=%s", kSAN_REGULAR);
	return false;
	}
	return true;
	}

	bool sanitizers_Init(honggfuzz_t* hfuzz) {
	if (hfuzz->linux.pid > 0) {
	return true;
	}

	if (hfuzz->enableSanitizers == false) {
	return sanitizers_Regular();
	}

	/* Set sanitizer flags once to avoid performance overhead per worker spawn */
	size_t flagsSz = 0;

	/* Larger constant combination + 2 dynamic paths */
	size_t bufSz = sizeof(kASAN_OPTS) + 1 + sizeof(kABORT_ENABLED) + 1 + sizeof(kSANLOGDIR) +
	PATH_MAX + 1 + sizeof(kSANCOVDIR) + PATH_MAX + 1;
	char* san_opts = util_Calloc(bufSz);
	defer { free(san_opts); };

	char* abortFlag;
	if (hfuzz->monitorSIGABRT) {
	abortFlag = kABORT_ENABLED;
	} else {
	abortFlag = kABORT_DISABLED;
	}

	/* Address Sanitizer (ASan) */
	if (hfuzz->useSanCov) {
	snprintf(san_opts, bufSz, "%s:%s:%s:%s%s/%s:%s%s/%s", kASAN_OPTS, abortFlag, kSAN_COV_OPTS,
	kSANCOVDIR, hfuzz->io.workDir, _HF_SANCOV_DIR, kSANLOGDIR, hfuzz->io.workDir,
	kLOGPREFIX);
	} else {
	snprintf(san_opts, bufSz, "%s:%s:%s%s/%s", kASAN_OPTS, abortFlag, kSANLOGDIR,
	hfuzz->io.workDir, kLOGPREFIX);
	}

	flagsSz = strlen(san_opts) + 1;
	hfuzz->sanOpts.asanOpts = util_Calloc(flagsSz);
	memcpy(hfuzz->sanOpts.asanOpts, san_opts, flagsSz);
	LOG_D("ASAN_OPTIONS=%s", hfuzz->sanOpts.asanOpts);

	/* Undefined Behavior Sanitizer (UBSan) */
	memset(san_opts, 0, bufSz);
	if (hfuzz->useSanCov) {
	snprintf(san_opts, bufSz, "%s:%s:%s:%s%s/%s:%s%s/%s", kUBSAN_OPTS, abortFlag, kSAN_COV_OPTS,
	kSANCOVDIR, hfuzz->io.workDir, _HF_SANCOV_DIR, kSANLOGDIR, hfuzz->io.workDir,
	kLOGPREFIX);
	} else {
	snprintf(san_opts, bufSz, "%s:%s:%s%s/%s", kUBSAN_OPTS, abortFlag, kSANLOGDIR,
	hfuzz->io.workDir, kLOGPREFIX);
	}

	flagsSz = strlen(san_opts) + 1;
	hfuzz->sanOpts.ubsanOpts = util_Calloc(flagsSz);
	memcpy(hfuzz->sanOpts.ubsanOpts, san_opts, flagsSz);
	LOG_D("UBSAN_OPTIONS=%s", hfuzz->sanOpts.ubsanOpts);

	/* Memory Sanitizer (MSan) */
	memset(san_opts, 0, bufSz);

	if (hfuzz->useSanCov) {
	snprintf(san_opts, bufSz, "%s:%s:%s:%s%s/%s:%s%s/%s", kMSAN_OPTS, abortFlag, kSAN_COV_OPTS,
	kSANCOVDIR, hfuzz->io.workDir, _HF_SANCOV_DIR, kSANLOGDIR, hfuzz->io.workDir,
	kLOGPREFIX);
	} else {
	snprintf(san_opts, bufSz, "%s:%s:%s%s/%s", kMSAN_OPTS, abortFlag, kSANLOGDIR,
	hfuzz->io.workDir, kLOGPREFIX);
	}

	flagsSz = strlen(san_opts) + 1;
	hfuzz->sanOpts.msanOpts = util_Calloc(flagsSz);
	memcpy(hfuzz->sanOpts.msanOpts, san_opts, flagsSz);
	LOG_D("MSAN_OPTIONS=%s", hfuzz->sanOpts.msanOpts);

	return true;
	}

	bool sanitizers_prepareExecve(run_t* run) {
	/* Address Sanitizer (ASan) */
	if (run->global->sanOpts.asanOpts) {
	if (setenv("ASAN_OPTIONS", run->global->sanOpts.asanOpts, 1) == -1) {
	PLOG_E("setenv(ASAN_OPTIONS) failed");
	return false;
	}
	}

	/* Memory Sanitizer (MSan) */
	if (run->global->sanOpts.msanOpts) {
	if (setenv("MSAN_OPTIONS", run->global->sanOpts.msanOpts, 1) == -1) {
	PLOG_E("setenv(MSAN_OPTIONS) failed");
	return false;
	}
	}

	/* Undefined Behavior Sanitizer (UBSan) */
	if (run->global->sanOpts.ubsanOpts) {
	if (setenv("UBSAN_OPTIONS", run->global->sanOpts.ubsanOpts, 1) == -1) {
	PLOG_E("setenv(UBSAN_OPTIONS) failed");
	return false;
	}
	}

	return true;
	}