pkg/csource: add freebsd/netbsd support

4 files changed, 652 insertions, 0 deletions

diff --git a/pkg/csource/csource.go b/pkg/csource/csource.go
index 6d06f101d..055a7466a 100644
--- a/pkg/csource/csource.go
+++ b/pkg/csource/csource.go
@@ -73,6 +73,10 @@ func Write(p *prog.Prog, opts Options) ([]byte, error) {
 		commonHeader = commonHeaderLinux
 	case "akaros":
 		commonHeader = commonHeaderAkaros
+	case "freebsd":
+		commonHeader = commonHeaderFreebsd
+	case "netbsd":
+		commonHeader = commonHeaderNetbsd
 	default:
 		return nil, fmt.Errorf("unsupported OS: %v", p.Target.OS)
 	}
diff --git a/pkg/csource/freebsd_common.go b/pkg/csource/freebsd_common.go
new file mode 100644
index 000000000..045ac9a89
--- /dev/null
+++ b/pkg/csource/freebsd_common.go
@@ -0,0 +1,321 @@
+// AUTOGENERATED FROM executor/common_bsd.h
+package csource
+
+var commonHeaderFreebsd = `
+
+
+#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 <stdint.h>
+#include <string.h>
+#if defined(SYZ_EXECUTOR) || defined(SYZ_USE_TMP_DIR)
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#endif
+#if defined(SYZ_EXECUTOR) || defined(SYZ_HANDLE_SEGV)
+#include <setjmp.h>
+#include <signal.h>
+#include <string.h>
+#endif
+#if defined(SYZ_EXECUTOR) || defined(SYZ_DEBUG)
+#include <stdarg.h>
+#include <stdio.h>
+#endif
+
+#if defined(SYZ_EXECUTOR)
+#define exit vsnprintf
+#define _exit vsnprintf
+#endif
+
+#if defined(SYZ_EXECUTOR)
+#if defined(__GNUC__)
+#define SYSCALLAPI
+#define NORETURN __attribute__((noreturn))
+#define ALIGNED(N) __attribute__((aligned(N)))
+#else
+#define SYSCALLAPI WINAPI
+#define NORETURN __declspec(noreturn)
+#define ALIGNED(N) __declspec(align(N))
+#endif
+
+typedef long(SYSCALLAPI* syscall_t)(long, long, long, long, long, long, long, long, long);
+
+struct call_t {
+	const char* name;
+	int sys_nr;
+	syscall_t call;
+};
+
+extern call_t syscalls[];
+extern unsigned syscall_count;
+#endif
+
+#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT)) ||            \
+    defined(SYZ_USE_TMP_DIR) || defined(SYZ_TUN_ENABLE) || defined(SYZ_SANDBOX_NAMESPACE) || \
+    defined(SYZ_SANDBOX_SETUID) || defined(SYZ_FAULT_INJECTION) || defined(__NR_syz_kvm_setup_cpu)
+const int kFailStatus = 67;
+const int kRetryStatus = 69;
+#endif
+
+#if defined(SYZ_EXECUTOR)
+const int kErrorStatus = 68;
+#endif
+
+#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT)) ||            \
+    defined(SYZ_USE_TMP_DIR) || defined(SYZ_TUN_ENABLE) || defined(SYZ_SANDBOX_NAMESPACE) || \
+    defined(SYZ_SANDBOX_SETUID) || defined(SYZ_FAULT_INJECTION) || defined(__NR_syz_kvm_setup_cpu)
+NORETURN static void fail(const char* msg, ...)
+{
+	int e = errno;
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fprintf(stderr, " (errno %d)\n", e);
+	doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR)
+NORETURN static void error(const char* msg, ...)
+{
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fprintf(stderr, "\n");
+	doexit(kErrorStatus);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT) && defined(SYZ_USE_TMP_DIR))
+NORETURN static void exitf(const char* msg, ...)
+{
+	int e = errno;
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fprintf(stderr, " (errno %d)\n", e);
+	doexit(kRetryStatus);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR) || defined(SYZ_DEBUG)
+static int flag_debug;
+
+static void debug(const char* msg, ...)
+{
+	if (!flag_debug)
+		return;
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fflush(stderr);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR) || defined(SYZ_USE_BITMASKS)
+#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)
+
+#define BITMASK_LEN_OFF(type, bf_off, bf_len) (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))
+
+#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)                         \
+	if ((bf_off) == 0 && (bf_len) == 0) {                                     \
+		*(type*)(addr) = (type)(val);                                     \
+	} else {                                                                  \
+		type new_val = *(type*)(addr);                                    \
+		new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));            \
+		new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off); \
+		*(type*)(addr) = new_val;                                         \
+	}
+#endif
+
+#if defined(SYZ_EXECUTOR) || defined(SYZ_USE_CHECKSUMS)
+struct csum_inet {
+	uint32_t acc;
+};
+
+static void csum_inet_init(struct csum_inet* csum)
+{
+	csum->acc = 0;
+}
+
+static void csum_inet_update(struct csum_inet* csum, const uint8_t* data, size_t length)
+{
+	if (length == 0)
+		return;
+
+	size_t i;
+	for (i = 0; i < length - 1; i += 2)
+		csum->acc += *(uint16_t*)&data[i];
+
+	if (length & 1)
+		csum->acc += (uint16_t)data[length - 1];
+
+	while (csum->acc > 0xffff)
+		csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16);
+}
+
+static uint16_t csum_inet_digest(struct csum_inet* csum)
+{
+	return ~csum->acc;
+}
+#endif
+
+#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)
+{
+	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", addr);
+		_longjmp(segv_env, 1);
+	}
+	debug("SIGSEGV on %p, exiting\n", addr);
+	doexit(sig);
+	for (;;) {
+	}
+}
+
+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_t current_time_ms()
+{
+	struct timespec ts;
+
+	if (clock_gettime(CLOCK_MONOTONIC, &ts))
+		fail("clock_gettime failed");
+	return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
+}
+#endif
+
+#if defined(SYZ_EXECUTOR)
+static void sleep_ms(uint64_t 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
+`
diff --git a/pkg/csource/gen.go b/pkg/csource/gen.go
index 103a6215e..24197c5d9 100644
--- a/pkg/csource/gen.go
+++ b/pkg/csource/gen.go
@@ -9,4 +9,10 @@
 //go:generate bash -c "echo -e '// AUTOGENERATED FROM executor/common_akaros.h\npackage csource\nvar commonHeaderAkaros = `' > akaros_common.go; cat ../../executor/common_akaros.h | sed -e '/#include \"common.h\"/ {' -e 'r ../../executor/common.h' -e 'd' -e '}' - | egrep -v '^[   ]*//' | sed '/^[ 	]*\\/\\/.*/d' | sed 's#[ 	]*//.*##g' >> akaros_common.go; echo '`' >> akaros_common.go"
 //go:generate go fmt akaros_common.go
 
+//go:generate bash -c "echo -e '// AUTOGENERATED FROM executor/common_bsd.h\npackage csource\nvar commonHeaderFreebsd = `' > freebsd_common.go; cat ../../executor/common_bsd.h | sed -e '/#include \"common.h\"/ {' -e 'r ../../executor/common.h' -e 'd' -e '}' - | egrep -v '^[   ]*//' | sed '/^[ 	]*\\/\\/.*/d' | sed 's#[ 	]*//.*##g' >> freebsd_common.go; echo '`' >> freebsd_common.go"
+//go:generate go fmt freebsd_common.go
+
+//go:generate bash -c "echo -e '// AUTOGENERATED FROM executor/common_bsd.h\npackage csource\nvar commonHeaderNetbsd = `' > netbsd_common.go; cat ../../executor/common_bsd.h | sed -e '/#include \"common.h\"/ {' -e 'r ../../executor/common.h' -e 'd' -e '}' - | egrep -v '^[   ]*//' | sed '/^[ 	]*\\/\\/.*/d' | sed 's#[ 	]*//.*##g' >> netbsd_common.go; echo '`' >> netbsd_common.go"
+//go:generate go fmt netbsd_common.go
+
 package csource
diff --git a/pkg/csource/netbsd_common.go b/pkg/csource/netbsd_common.go
new file mode 100644
index 000000000..a83bf578c
--- /dev/null
+++ b/pkg/csource/netbsd_common.go
@@ -0,0 +1,321 @@
+// AUTOGENERATED FROM executor/common_bsd.h
+package csource
+
+var commonHeaderNetbsd = `
+
+
+#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 <stdint.h>
+#include <string.h>
+#if defined(SYZ_EXECUTOR) || defined(SYZ_USE_TMP_DIR)
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#endif
+#if defined(SYZ_EXECUTOR) || defined(SYZ_HANDLE_SEGV)
+#include <setjmp.h>
+#include <signal.h>
+#include <string.h>
+#endif
+#if defined(SYZ_EXECUTOR) || defined(SYZ_DEBUG)
+#include <stdarg.h>
+#include <stdio.h>
+#endif
+
+#if defined(SYZ_EXECUTOR)
+#define exit vsnprintf
+#define _exit vsnprintf
+#endif
+
+#if defined(SYZ_EXECUTOR)
+#if defined(__GNUC__)
+#define SYSCALLAPI
+#define NORETURN __attribute__((noreturn))
+#define ALIGNED(N) __attribute__((aligned(N)))
+#else
+#define SYSCALLAPI WINAPI
+#define NORETURN __declspec(noreturn)
+#define ALIGNED(N) __declspec(align(N))
+#endif
+
+typedef long(SYSCALLAPI* syscall_t)(long, long, long, long, long, long, long, long, long);
+
+struct call_t {
+	const char* name;
+	int sys_nr;
+	syscall_t call;
+};
+
+extern call_t syscalls[];
+extern unsigned syscall_count;
+#endif
+
+#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT)) ||            \
+    defined(SYZ_USE_TMP_DIR) || defined(SYZ_TUN_ENABLE) || defined(SYZ_SANDBOX_NAMESPACE) || \
+    defined(SYZ_SANDBOX_SETUID) || defined(SYZ_FAULT_INJECTION) || defined(__NR_syz_kvm_setup_cpu)
+const int kFailStatus = 67;
+const int kRetryStatus = 69;
+#endif
+
+#if defined(SYZ_EXECUTOR)
+const int kErrorStatus = 68;
+#endif
+
+#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT)) ||            \
+    defined(SYZ_USE_TMP_DIR) || defined(SYZ_TUN_ENABLE) || defined(SYZ_SANDBOX_NAMESPACE) || \
+    defined(SYZ_SANDBOX_SETUID) || defined(SYZ_FAULT_INJECTION) || defined(__NR_syz_kvm_setup_cpu)
+NORETURN static void fail(const char* msg, ...)
+{
+	int e = errno;
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fprintf(stderr, " (errno %d)\n", e);
+	doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR)
+NORETURN static void error(const char* msg, ...)
+{
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fprintf(stderr, "\n");
+	doexit(kErrorStatus);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR) || (defined(SYZ_REPEAT) && defined(SYZ_WAIT_REPEAT) && defined(SYZ_USE_TMP_DIR))
+NORETURN static void exitf(const char* msg, ...)
+{
+	int e = errno;
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fprintf(stderr, " (errno %d)\n", e);
+	doexit(kRetryStatus);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR) || defined(SYZ_DEBUG)
+static int flag_debug;
+
+static void debug(const char* msg, ...)
+{
+	if (!flag_debug)
+		return;
+	va_list args;
+	va_start(args, msg);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+	fflush(stderr);
+}
+#endif
+
+#if defined(SYZ_EXECUTOR) || defined(SYZ_USE_BITMASKS)
+#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)
+
+#define BITMASK_LEN_OFF(type, bf_off, bf_len) (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))
+
+#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)                         \
+	if ((bf_off) == 0 && (bf_len) == 0) {                                     \
+		*(type*)(addr) = (type)(val);                                     \
+	} else {                                                                  \
+		type new_val = *(type*)(addr);                                    \
+		new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));            \
+		new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off); \
+		*(type*)(addr) = new_val;                                         \
+	}
+#endif
+
+#if defined(SYZ_EXECUTOR) || defined(SYZ_USE_CHECKSUMS)
+struct csum_inet {
+	uint32_t acc;
+};
+
+static void csum_inet_init(struct csum_inet* csum)
+{
+	csum->acc = 0;
+}
+
+static void csum_inet_update(struct csum_inet* csum, const uint8_t* data, size_t length)
+{
+	if (length == 0)
+		return;
+
+	size_t i;
+	for (i = 0; i < length - 1; i += 2)
+		csum->acc += *(uint16_t*)&data[i];
+
+	if (length & 1)
+		csum->acc += (uint16_t)data[length - 1];
+
+	while (csum->acc > 0xffff)
+		csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16);
+}
+
+static uint16_t csum_inet_digest(struct csum_inet* csum)
+{
+	return ~csum->acc;
+}
+#endif
+
+#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)
+{
+	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", addr);
+		_longjmp(segv_env, 1);
+	}
+	debug("SIGSEGV on %p, exiting\n", addr);
+	doexit(sig);
+	for (;;) {
+	}
+}
+
+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_t current_time_ms()
+{
+	struct timespec ts;
+
+	if (clock_gettime(CLOCK_MONOTONIC, &ts))
+		fail("clock_gettime failed");
+	return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
+}
+#endif
+
+#if defined(SYZ_EXECUTOR)
+static void sleep_ms(uint64_t 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
+`