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// Copyright 2017 syzkaller project authors. All rights reserved.
// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
// This file is shared between executor and csource package.
#include <unistd.h>
#if defined(SYZ_EXECUTOR) || defined(SYZ_THREADED) || defined(SYZ_COLLIDE)
#include <pthread.h>
#include <stdlib.h>
#endif
#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT))
#include <errno.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <time.h>
#endif
#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT) && defined(SYZ_USE_TMP_DIR))
#include <dirent.h>
#endif
#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT)) || \
defined(SYZ_USE_TMP_DIR) || defined(SYZ_HANDLE_SEGV) || defined(SYZ_TUN_ENABLE) || \
defined(SYZ_SANDBOX_NAMESPACE) || defined(SYZ_SANDBOX_SETUID) || \
defined(SYZ_SANDBOX_NONE) || defined(SYZ_FAULT_INJECTION) || defined(__NR_syz_kvm_setup_cpu)
__attribute__((noreturn)) static void doexit(int status)
{
_exit(status);
for (;;) {
}
}
#endif
#include "common.h"
#if defined(SYZ_EXECUTOR) || defined(SYZ_HANDLE_SEGV)
static __thread int skip_segv;
static __thread jmp_buf segv_env;
static void segv_handler(int sig, siginfo_t* info, void* uctx)
{
// Generated programs can contain bad (unmapped/protected) addresses,
// which cause SIGSEGVs during copyin/copyout.
// This handler ignores such crashes to allow the program to proceed.
// We additionally opportunistically check that the faulty address
// is not within executable data region, because such accesses can corrupt
// output region and then fuzzer will fail on corrupted data.
uintptr_t addr = (uintptr_t)info->si_addr;
const uintptr_t prog_start = 1 << 20;
const uintptr_t prog_end = 100 << 20;
if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && (addr < prog_start || addr > prog_end)) {
debug("SIGSEGV on %p, skipping\n", (void*)addr);
_longjmp(segv_env, 1);
}
debug("SIGSEGV on %p, exiting\n", (void*)addr);
doexit(sig);
}
static void install_segv_handler()
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = segv_handler;
sa.sa_flags = SA_NODEFER | SA_SIGINFO;
sigaction(SIGSEGV, &sa, NULL);
sigaction(SIGBUS, &sa, NULL);
}
#define NONFAILING(...) \
{ \
__atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \
if (_setjmp(segv_env) == 0) { \
__VA_ARGS__; \
} \
__atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \
}
#endif
#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT))
static uint64 current_time_ms()
{
struct timespec ts;
if (clock_gettime(CLOCK_MONOTONIC, &ts))
fail("clock_gettime failed");
return (uint64)ts.tv_sec * 1000 + (uint64)ts.tv_nsec / 1000000;
}
#endif
#if defined(SYZ_EXECUTOR)
static void sleep_ms(uint64 ms)
{
usleep(ms * 1000);
}
#endif
#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT) && defined(SYZ_USE_TMP_DIR))
static void remove_dir(const char* dir)
{
DIR* dp;
struct dirent* ep;
int iter = 0;
retry:
dp = opendir(dir);
if (dp == NULL)
return;
while ((ep = readdir(dp))) {
if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0)
continue;
char filename[FILENAME_MAX];
snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name);
struct stat st;
if (lstat(filename, &st))
return;
if (S_ISDIR(st.st_mode)) {
remove_dir(filename);
continue;
}
int i;
for (i = 0;; i++) {
if (unlink(filename) == 0)
break;
if (errno == EROFS)
break;
if (errno != EBUSY || i > 100)
return;
}
}
closedir(dp);
int i;
for (i = 0;; i++) {
if (rmdir(dir) == 0)
break;
if (i < 100) {
if (errno == EROFS)
break;
if (errno == ENOTEMPTY) {
if (iter < 100) {
iter++;
goto retry;
}
}
}
return;
}
}
#endif
#if defined(SYZ_EXECUTOR) || defined(SYZ_FAULT_INJECTION)
static int inject_fault(int nth)
{
return 0;
}
static int fault_injected(int fail_fd)
{
return 0;
}
#endif
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