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mtfuzz.c
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mtfuzz.c
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#define _GNU_SOURCE
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <sched.h>
#include <sys/stat.h>
#include <string.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <string.h>
#include <stdint.h>
#include <sys/mman.h>
#include <dirent.h>
#include <ctype.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <time.h>
/* Most of code is borrowed directly from AFL fuzzer (https://github.com/mirrorer/afl), credits to Michal Zalewski */
/* Fork server init timeout multiplier: we'll wait the user-selected timeout plus this much for the fork server to spin up. */
#define FORK_WAIT_MULT 10
/* Environment variable used to pass SHM ID to the called program. */
#define SHM_ENV_VAR "__AFL_SHM_ID"
/* Local port to communicate with python module. */
#define PORT 12012
/* Maximum line length passed from GCC to 'as' and used for parsing configuration files. */
#define MAX_LINE 8192
/* Designated file descriptors for forkserver commands (the application will use FORKSRV_FD and FORKSRV_FD + 1). */
#define FORKSRV_FD 198
/* Distinctive bitmap signature used to indicate failed execution. */
#define EXEC_FAIL_SIG 0xfee1dead
/* Smoothing divisor for CPU load and exec speed stats (1 - no smoothing). */
#define AVG_SMOOTHING 16
/* Caps on block sizes for inserion and deletion operations. The set of numbers are adaptive to file length and the defalut max file length is 10000. */
/* default setting, will be changed later accroding to file len */
int havoc_blk_small = 2048;
int havoc_blk_medium = 4096;
int havoc_blk_large = 8192;
#define HAVOC_BLK_SMALL 2048
#define HAVOC_BLK_MEDIUM 4096
#define HAVOC_BLK_LARGE 7402
#define MEM_BARRIER() \
asm volatile("" ::: "memory")
/* Map size for the traced binary. */
#define MAP_SIZE 2<<18
#define R(x) (random() % (x))
#define likely(_x) __builtin_expect(!!(_x), 1)
#define unlikely(_x) __builtin_expect(!!(_x), 0)
#define MIN(_a,_b) ((_a) > (_b) ? (_b) : (_a))
#define MAX(_a,_b) ((_a) > (_b) ? (_a) : (_b))
/* Error-checking versions of read() and write() that call RPFATAL() as appropriate. */
#define ck_write(fd, buf, len, fn) do { \
u32 _len = (len); \
int _res = write(fd, buf, _len); \
if (_res != _len) fprintf(stderr, "Short write to %d %s\n",_res, fn); \
} while (0)
#define ck_read(fd, buf, len, fn) do { \
u32 _len = (len); \
int _res = read(fd, buf, _len); \
if (_res != _len) fprintf(stderr, "Short read from %d %s\n",_res, fn); \
} while (0)
/* User-facing macro to sprintf() to a dynamically allocated buffer. */
#define alloc_printf(_str...) ({ \
char* _tmp; \
int _len = snprintf(NULL, 0, _str); \
if (_len < 0) perror("Whoa, snprintf() fails?!"); \
_tmp = malloc(_len + 1); \
snprintf((char*)_tmp, _len + 1, _str); \
_tmp; \
})
typedef uint8_t u8;
typedef uint16_t u16;
typedef uint32_t u32;
#ifdef __x86_64__
typedef unsigned long long u64;
#else
typedef uint64_t u64;
#endif /* ^__x86_64__ */
unsigned long total_execs; /* Total number of execs */
static int shm_id; /* ID of the SHM region */
static int mem_limit = 1024; /* Maximum memory limit for target program */
static int cpu_aff = -1; /* Selected CPU core */
int round_cnt = 0; /* Round number counter */
int edge_gain=0; /* If there is new edge gain */
int exec_tmout = 1000; /* Exec timeout (ms) */
int old=0;
int now=0;
int fast=1;
char * target_path; /* Path to target binary */
char * trace_bits; /* SHM with instrumentation bitmap */
static volatile int stop_soon; /* Ctrl-C pressed? */
static int cpu_core_count; /* CPU core count */
static u64 total_cal_us=0; /* Total calibration time (us) */
static volatile int child_timed_out; /* Traced process timed out? */
int kill_signal; /* Signal that killed the child */
static int out_fd, /* Persistent fd for out_file */
dev_urandom_fd = -1, /* Persistent fd for /dev/urandom */
dev_null_fd = -1, /* Persistent fd for /dev/null */
fsrv_ctl_fd, /* Fork server control pipe (write) */
fsrv_st_fd; /* Fork server status pipe (read) */
static int forksrv_pid, /* PID of the fork server */
child_pid = -1, /* PID of the fuzzed program */
out_dir_fd = -1; /* FD of the lock file */
char *in_dir, /* Input directory with test cases */
*out_file, /* File to fuzz, if any */
*out_dir; /* Working & output directory */
char virgin_bits[MAP_SIZE]; /* Regions yet untouched by fuzzing */
static int mut_cnt = 0; /* Total mutation counter */
char *out_buf, *out_buf1, *out_buf2, *out_buf3;
size_t len; /* Maximum file length for every mutation */
int loc[10000]; /* Array to store critical bytes locations*/
int sign[10000]; /* Array to store sign of critical bytes */
/* more fined grined mutation can have better results but slower*/
//int num_index[23] = {0,2,4,8,16,32,64,128,256,512,1024,1536,2048,2560,3072, 3584,4096,4608,5120, 5632,6144,6656,7103};
/* default setting, will be change according to different file length */
int num_index[14] = {0,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192};
enum {
/* 00 */ FAULT_NONE,
/* 01 */ FAULT_TMOUT,
/* 02 */ FAULT_CRASH,
/* 03 */ FAULT_ERROR,
/* 04 */ FAULT_NOINST,
/* 05 */ FAULT_NOBITS
};
/* Spin up fork server (instrumented mode only). The idea is explained here:
http://lcamtuf.blogspot.com/2014/10/fuzzing-binaries-without-execve.html
In essence, the instrumentation allows us to skip execve(), and just keep
cloning a stopped child. So, we just execute once, and then send commands
through a pipe. The other part of this logic is in afl-as.h. */
void setup_stdio_file(void) {
char* fn = alloc_printf("%s/.cur_input", out_dir);
unlink(fn); /* Ignore errors */
out_fd = open(fn, O_RDWR | O_CREAT | O_EXCL, 0600);
if (out_fd < 0) perror("Unable to create .cur_input");
}
/* Count the number of non-255 bytes set in the bitmap. Used strictly for the
status screen, several calls per second or so. */
#define FF(_b) (0xff << ((_b) << 3))
static u32 count_non_255_bytes(u8* mem) {
u32* ptr = (u32*)mem;
u32 i = (MAP_SIZE >> 2);
u32 ret = 0;
while (i--) {
u32 v = *(ptr++);
/* This is called on the virgin bitmap, so optimize for the most likely
case. */
if (v == 0xffffffff) continue;
if ((v & FF(0)) != FF(0)) ret++;
if ((v & FF(1)) != FF(1)) ret++;
if ((v & FF(2)) != FF(2)) ret++;
if ((v & FF(3)) != FF(3)) ret++;
}
return ret;
}
/* Handle stop signal (Ctrl-C, etc). */
static void handle_stop_sig(int sig) {
stop_soon = 1;
if (child_pid > 0) kill(child_pid, SIGKILL);
if (forksrv_pid > 0) kill(forksrv_pid, SIGKILL);
printf("total execs %ld edge coverage %d.\n", total_execs,(int)(count_non_255_bytes(virgin_bits)));
//free buffer
free(out_buf);
free(out_buf1);
free(out_buf2);
free(out_buf3);
exit(0);
}
/* Check if the current execution path brings anything new to the table.
Update virgin bits to reflect the finds. Returns 1 if the only change is
the hit-count for a particular tuple; 2 if there are new tuples seen.
Updates the map, so subsequent calls will always return 0.
This function is called after every exec() on a fairly large buffer, so
it needs to be fast. We do this in 32-bit and 64-bit flavors. */
static inline char has_new_bits(char* virgin_map) {
#ifdef __x86_64__
u64* current = (u64*)trace_bits;
u64* virgin = (u64*)virgin_map;
u32 i = (MAP_SIZE >> 3);
#else
u32* current = (u32*)trace_bits;
u32* virgin = (u32*)virgin_map;
u32 i = (MAP_SIZE >> 2);
#endif /* ^__x86_64__ */
u8 ret = 0;
while (i--) {
/* Optimize for (*current & *virgin) == 0 - i.e., no bits in current bitmap
that have not been already cleared from the virgin map - since this will
almost always be the case. */
if (unlikely(*current) && unlikely(*current & *virgin)) {
if (likely(ret < 2)) {
u8* cur = (u8*)current;
u8* vir = (u8*)virgin;
/* Looks like we have not found any new bytes yet; see if any non-zero
bytes in current[] are pristine in virgin[]. */
#ifdef __x86_64__
if ((cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
(cur[2] && vir[2] == 0xff) || (cur[3] && vir[3] == 0xff) ||
(cur[4] && vir[4] == 0xff) || (cur[5] && vir[5] == 0xff) ||
(cur[6] && vir[6] == 0xff) || (cur[7] && vir[7] == 0xff)) ret = 2;
else ret = 1;
#else
if ((cur[0] && vir[0] == 0xff) || (cur[1] && vir[1] == 0xff) ||
(cur[2] && vir[2] == 0xff) || (cur[3] && vir[3] == 0xff)) ret = 2;
else ret = 1;
#endif /* ^__x86_64__ */
}
*virgin &= ~*current;
}
current++;
virgin++;
}
return ret;
}
/* Handle timeout (SIGALRM). */
static void handle_timeout(int sig) {
if (child_pid > 0) {
child_timed_out = 1;
kill(child_pid, SIGKILL);
} else if (child_pid == -1 && forksrv_pid > 0) {
child_timed_out = 1;
kill(forksrv_pid, SIGKILL);
}
}
/* Set up signal handlers. More complicated that needs to be, because libc on
Solaris doesn't resume interrupted reads(), sets SA_RESETHAND when you call
siginterrupt(), and does other stupid things. */
void setup_signal_handlers(void) {
struct sigaction sa;
sa.sa_handler = NULL;
sa.sa_flags = SA_RESTART;
sa.sa_sigaction = NULL;
sigemptyset(&sa.sa_mask);
/* Various ways of saying "stop". */
sa.sa_handler = handle_stop_sig;
sigaction(SIGHUP, &sa, NULL);
sigaction(SIGINT, &sa, NULL);
sigaction(SIGTERM, &sa, NULL);
/* Exec timeout notifications. */
sa.sa_handler = handle_timeout;
sigaction(SIGALRM, &sa, NULL);
/* Things we don't care about. */
sa.sa_handler = SIG_IGN;
sigaction(SIGTSTP, &sa, NULL);
sigaction(SIGPIPE, &sa, NULL);
}
void init_forkserver(char** argv) {
static struct itimerval it;
int st_pipe[2], ctl_pipe[2];
int status;
int rlen;
char* cwd = getcwd(NULL, 0);
//out_file = "/dev/shm/dd/.cur_input";
out_file = alloc_printf("%s/%s/.cur_input",cwd, out_dir);
printf("Spinning up the fork server...\n");
if (pipe(st_pipe) || pipe(ctl_pipe)) perror("pipe() failed");
forksrv_pid = fork();
if (forksrv_pid < 0) perror("fork() failed");
if (!forksrv_pid) {
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 (mem_limit) {
r.rlim_max = r.rlim_cur = ((rlim_t)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 out_file is
specified, stdin is /dev/null; otherwise, out_fd is cloned instead. */
setsid();
dup2(dev_null_fd, 1);
dup2(dev_null_fd, 2);
if (out_file) {
dup2(dev_null_fd, 0);
} else {
dup2(out_fd, 0);
close(out_fd);
}
/* Set up control and status pipes, close the unneeded original fds. */
if (dup2(ctl_pipe[0], FORKSRV_FD) < 0) perror("dup2() failed");
if (dup2(st_pipe[1], FORKSRV_FD + 1) < 0) perror("dup2() failed");
close(ctl_pipe[0]);
close(ctl_pipe[1]);
close(st_pipe[0]);
close(st_pipe[1]);
close(out_dir_fd);
close(dev_null_fd);
close(dev_urandom_fd);
/* 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);
execv(target_path, argv);
/* Use a distinctive bitmap signature to tell the parent about execv()
falling through. */
*(int *)trace_bits = EXEC_FAIL_SIG;
exit(0);
}
/* Close the unneeded endpoints. */
close(ctl_pipe[0]);
close(st_pipe[1]);
fsrv_ctl_fd = ctl_pipe[1];
fsrv_st_fd = st_pipe[0];
/* Wait for the fork server to come up, but don't wait too long. */
it.it_value.tv_sec = ((exec_tmout * FORK_WAIT_MULT) / 1000);
it.it_value.tv_usec = ((exec_tmout * FORK_WAIT_MULT) % 1000) * 1000;
setitimer(ITIMER_REAL, &it, NULL);
rlen = read(fsrv_st_fd, &status, 4);
it.it_value.tv_sec = 0;
it.it_value.tv_usec = 0;
setitimer(ITIMER_REAL, &it, NULL);
/* If we have a four-byte "hello" message from the server, we're all set.
Otherwise, try to figure out what went wrong. */
if (rlen == 4) {
printf("All right - fork server is up.");
return;
}
if (child_timed_out)
perror("Timeout while initializing fork server (adjusting -t may help)");
if (waitpid(forksrv_pid, &status, 0) <= 0)
perror("waitpid() failed");
if (WIFSIGNALED(status)) {
fprintf(stderr, "Fork server crashed with signal %d", WTERMSIG(status));
}
if (*(int*)trace_bits == EXEC_FAIL_SIG)
fprintf(stderr, "Unable to execute target application ('%s')", argv[0]);
perror("Fork server handshake failed");
}
/* Get rid of shared memory (atexit handler). */
static void remove_shm(void) {
shmctl(shm_id, IPC_RMID, NULL);
}
/* Configure shared memory and virgin_bits. This is called at startup. */
void setup_shm(void) {
char* shm_str;
memset(virgin_bits, 255, MAP_SIZE);
shm_id = shmget(IPC_PRIVATE, MAP_SIZE, IPC_CREAT | IPC_EXCL | 0600);
if (shm_id < 0) perror("shmget() failed");
atexit(remove_shm);
shm_str = alloc_printf("%d", shm_id);
/* If somebody is asking us to fuzz instrumented binaries in dumb mode,
we don't want them to detect instrumentation, since we won't be sending
fork server commands. This should be replaced with better auto-detection
later on, perhaps? */
setenv(SHM_ENV_VAR, shm_str, 1);
free(shm_str);
trace_bits = shmat(shm_id, NULL, 0);
if (!trace_bits) perror("shmat() failed");
}
void setup_dirs_fds(void) {
char* tmp;
int fd;
printf("Setting up output directories...");
if (mkdir(out_dir, 0700)) {
if (errno != EEXIST) fprintf(stderr,"Unable to create %s\n", out_dir);
}
/* Generally useful file descriptors. */
dev_null_fd = open("/dev/null", O_RDWR);
if (dev_null_fd < 0) perror("Unable to open /dev/null");
dev_urandom_fd = open("/dev/urandom", O_RDONLY);
if (dev_urandom_fd < 0) perror("Unable to open /dev/urandom");
}
/* Detect @@ in args. */
void detect_file_args(char** argv) {
int i = 0;
char* cwd = getcwd(NULL, 0);
if (!cwd) perror("getcwd() failed");
while (argv[i]) {
char* aa_loc = strstr(argv[i], "@@");
if (aa_loc) {
char *aa_subst, *n_arg;
/* If we don't have a file name chosen yet, use a safe default. */
if (!out_file)
//out_file = "/dev/shm/dd/.cur_input";
out_file = alloc_printf("%s/.cur_input", out_dir);
/* Be sure that we're always using fully-qualified paths. */
if (out_file[0] == '/') aa_subst = out_file;
else aa_subst = alloc_printf("%s/%s", cwd, out_file);
/* Construct a replacement argv value. */
*aa_loc = 0;
n_arg = alloc_printf("%s%s%s", argv[i], aa_subst, aa_loc + 2);
argv[i] = n_arg;
*aa_loc = '@';
if (out_file[0] != '/') free(aa_subst);
}
i++;
}
free(cwd); /* not tracked */
}
/* set up target path */
void setup_targetpath(char * argvs){
char* cwd = getcwd(NULL, 0);
target_path = alloc_printf("%s/%s", cwd, argvs);
argvs = target_path;
}
/* Destructively classify execution counts in a trace. This is used as a
preprocessing step for any newly acquired traces. Called on every exec,
must be fast. */
static const u8 count_class_lookup8[256] = {
[0] = 0,
[1] = 1,
[2] = 2,
[3] = 4,
[4 ... 7] = 8,
[8 ... 15] = 16,
[16 ... 31] = 32,
[32 ... 127] = 64,
[128 ... 255] = 128
};
static u16 count_class_lookup16[65536];
void init_count_class16(void) {
u32 b1, b2;
for (b1 = 0; b1 < 256; b1++)
for (b2 = 0; b2 < 256; b2++)
count_class_lookup16[(b1 << 8) + b2] =
(count_class_lookup8[b1] << 8) |
count_class_lookup8[b2];
}
#ifdef __x86_64__
static inline void classify_counts(u64* mem) {
u32 i = MAP_SIZE >> 3;
while (i--) {
/* Optimize for sparse bitmaps. */
if (unlikely(*mem)) {
u16* mem16 = (u16*)mem;
mem16[0] = count_class_lookup16[mem16[0]];
mem16[1] = count_class_lookup16[mem16[1]];
mem16[2] = count_class_lookup16[mem16[2]];
mem16[3] = count_class_lookup16[mem16[3]];
}
mem++;
}
}
#else
static inline void classify_counts(u32* mem) {
u32 i = MAP_SIZE >> 2;
while (i--) {
/* Optimize for sparse bitmaps. */
if (unlikely(*mem)) {
u16* mem16 = (u16*)mem;
mem16[0] = count_class_lookup16[mem16[0]];
mem16[1] = count_class_lookup16[mem16[1]];
}
mem++;
}
}
#endif /* ^__x86_64__ */
/* Get the number of runnable processes, with some simple smoothing. */
static double get_runnable_processes(void) {
static double res;
#if defined(__APPLE__) || defined(__FreeBSD__) || defined (__OpenBSD__)
/* I don't see any portable sysctl or so that would quickly give us the
number of runnable processes; the 1-minute load average can be a
semi-decent approximation, though. */
if (getloadavg(&res, 1) != 1) return 0;
#else
/* On Linux, /proc/stat is probably the best way; load averages are
computed in funny ways and sometimes don't reflect extremely short-lived
processes well. */
FILE* f = fopen("/proc/stat", "r");
u8 tmp[1024];
u32 val = 0;
if (!f) return 0;
while (fgets(tmp, sizeof(tmp), f)) {
if (!strncmp(tmp, "procs_running ", 14) ||
!strncmp(tmp, "procs_blocked ", 14)) val += atoi(tmp + 14);
}
fclose(f);
if (!res) {
res = val;
} else {
res = res * (1.0 - 1.0 / AVG_SMOOTHING) +
((double)val) * (1.0 / AVG_SMOOTHING);
}
#endif /* ^(__APPLE__ || __FreeBSD__ || __OpenBSD__) */
return res;
}
/* Count the number of logical CPU cores. */
static void get_core_count(void) {
u32 cur_runnable = 0;
#if defined(__APPLE__) || defined(__FreeBSD__) || defined (__OpenBSD__)
size_t s = sizeof(cpu_core_count);
/* On *BSD systems, we can just use a sysctl to get the number of CPUs. */
#ifdef __APPLE__
if (sysctlbyname("hw.logicalcpu", &cpu_core_count, &s, NULL, 0) < 0)
return;
#else
int s_name[2] = { CTL_HW, HW_NCPU };
if (sysctl(s_name, 2, &cpu_core_count, &s, NULL, 0) < 0) return;
#endif /* ^__APPLE__ */
#else
#ifdef HAVE_AFFINITY
cpu_core_count = sysconf(_SC_NPROCESSORS_ONLN);
#else
FILE* f = fopen("/proc/stat", "r");
u8 tmp[1024];
if (!f) return;
while (fgets(tmp, sizeof(tmp), f))
if (!strncmp(tmp, "cpu", 3) && isdigit(tmp[3])) cpu_core_count++;
fclose(f);
#endif /* ^HAVE_AFFINITY */
#endif /* ^(__APPLE__ || __FreeBSD__ || __OpenBSD__) */
if (cpu_core_count > 0) {
cur_runnable = (u32)get_runnable_processes();
#if defined(__APPLE__) || defined(__FreeBSD__) || defined (__OpenBSD__)
/* Add ourselves, since the 1-minute average doesn't include that yet. */
cur_runnable++;
#endif /* __APPLE__ || __FreeBSD__ || __OpenBSD__ */
printf("You have %u CPU core%s and %u runnable tasks (utilization: %0.0f%%).\n",
cpu_core_count, cpu_core_count > 1 ? "s" : "",
cur_runnable, cur_runnable * 100.0 / cpu_core_count);
if (cpu_core_count > 1) {
if (cur_runnable > cpu_core_count * 1.5) {
printf("System under apparent load, performance may be spotty.\n");
}
}
} else {
cpu_core_count = 0;
printf("Unable to figure out the number of CPU cores.\n");
}
}
/* Build a list of processes bound to specific cores. Returns -1 if nothing
can be found. Assumes an upper bound of 4k CPUs. */
static void bind_to_free_cpu(void) {
DIR* d;
struct dirent* de;
cpu_set_t c;
u8 cpu_used[4096] = { 0 };
u32 i;
if (cpu_core_count < 2) return;
if (getenv("AFL_NO_AFFINITY")) {
perror("Not binding to a CPU core (AFL_NO_AFFINITY set).");
return;
}
d = opendir("/proc");
if (!d) {
perror("Unable to access /proc - can't scan for free CPU cores.");
return;
}
printf("Checking CPU core loadout...\n");
/* Introduce some jitter, in case multiple AFL tasks are doing the same
thing at the same time... */
usleep(R(1000) * 250);
/* Scan all /proc/<pid>/status entries, checking for Cpus_allowed_list.
Flag all processes bound to a specific CPU using cpu_used[]. This will
fail for some exotic binding setups, but is likely good enough in almost
all real-world use cases. */
while ((de = readdir(d))) {
u8* fn;
FILE* f;
u8 tmp[MAX_LINE];
u8 has_vmsize = 0;
if (!isdigit(de->d_name[0])) continue;
fn = alloc_printf("/proc/%s/status", de->d_name);
if (!(f = fopen(fn, "r"))) {
free(fn);
continue;
}
while (fgets(tmp, MAX_LINE, f)) {
u32 hval;
/* Processes without VmSize are probably kernel tasks. */
if (!strncmp(tmp, "VmSize:\t", 8)) has_vmsize = 1;
if (!strncmp(tmp, "Cpus_allowed_list:\t", 19) &&
!strchr(tmp, '-') && !strchr(tmp, ',') &&
sscanf(tmp + 19, "%u", &hval) == 1 && hval < sizeof(cpu_used) &&
has_vmsize) {
cpu_used[hval] = 1;
break;
}
}
free(fn);
fclose(f);
}
closedir(d);
for (i = 0; i < cpu_core_count; i++) if (!cpu_used[i]) break;
if (i == cpu_core_count) {
printf("No more free CPU cores\n");
}
printf("Found a free CPU core, binding to #%u.\n", i);
cpu_aff = i;
CPU_ZERO(&c);
CPU_SET(i, &c);
if (sched_setaffinity(0, sizeof(c), &c))
perror("sched_setaffinity failed\n");
}
/* Get unix time in microseconds */
static u64 get_cur_time_us(void) {
struct timeval tv;
struct timezone tz;
gettimeofday(&tv, &tz);
return (tv.tv_sec * 1000000ULL) + tv.tv_usec;
}
/* Execute target application, monitoring for timeouts. Return status
information. The called program will update trace_bits[]. */
static u8 run_target(int timeout) {
static struct itimerval it;
static u32 prev_timed_out = 0;
int status = 0;
child_timed_out = 0;
/* After this memset, trace_bits[] are effectively volatile, so we
must prevent any earlier operations from venturing into that
territory. */
memset(trace_bits, 0, MAP_SIZE);
MEM_BARRIER();
int res;
/* In non-dumb mode, we have the fork server up and running, so simply
tell it to have at it, and then read back PID. */
if ((res = write(fsrv_ctl_fd, &prev_timed_out, 4)) != 4) {
if (stop_soon) return 0;
fprintf(stderr,"err%d: Unable to request new process from fork server (OOM?)", res);
}
if ((res = read(fsrv_st_fd, &child_pid, 4)) != 4) {
if (stop_soon) return 0;
fprintf(stderr, "err%d: Unable to request new process from fork server (OOM?)",res);
}
if (child_pid <= 0) perror("Fork server is misbehaving (OOM?)");
/* Configure timeout, as requested by user, then wait for child to terminate. */
it.it_value.tv_sec = (timeout / 1000);
it.it_value.tv_usec = (timeout % 1000) * 1000;
setitimer(ITIMER_REAL, &it, NULL);
/* The SIGALRM handler simply kills the child_pid and sets child_timed_out. */