// autogenerated by syzkaller (http://github.com/google/syzkaller) #ifndef __NR_setsockopt #define __NR_setsockopt 54 #endif #ifndef __NR_mmap #define __NR_mmap 9 #endif #ifndef __NR_socket #define __NR_socket 41 #endif #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include const int kFailStatus = 67; const int kErrorStatus = 68; const int kRetryStatus = 69; __attribute__((noreturn)) void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } __attribute__((noreturn)) void fail(const char* msg, ...) { int e = errno; fflush(stdout); 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); } __attribute__((noreturn)) void exitf(const char* msg, ...) { int e = errno; fflush(stdout); va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit(kRetryStatus); } static int flag_debug; void debug(const char* msg, ...) { if (!flag_debug) return; va_list args; va_start(args, msg); vfprintf(stdout, msg, args); va_end(args); fflush(stdout); } __thread int skip_segv; __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); \ } #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; \ } static uintptr_t execute_syscall(int nr, uintptr_t a0, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintptr_t a4, uintptr_t a5, uintptr_t a6, uintptr_t a7, uintptr_t a8) { switch (nr) { default: return syscall(nr, a0, a1, a2, a3, a4, a5); } } static void setup_main_process() { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); install_segv_handler(); char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_IO); } static int do_sandbox_none(int executor_pid, bool enable_tun) { int pid = fork(); if (pid) return pid; sandbox_common(); loop(); doexit(1); } long r[5]; void loop() { memset(r, -1, sizeof(r)); r[0] = execute_syscall(__NR_mmap, 0x2000e000ul, 0x1000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul, 0, 0, 0); r[1] = execute_syscall(__NR_mmap, 0x2000f000ul, 0x1000ul, 0x1ul, 0x32ul, 0xfffffffffffffffful, 0x0ul, 0, 0, 0); r[2] = execute_syscall(__NR_socket, 0xaul, 0x2ul, 0x0ul, 0, 0, 0, 0, 0, 0); NONFAILING(memcpy( (void*)0x2000ef92, "\x7c\x14\x04\x00\x00\x00\x07\x97\xee\x0a\xf4\x64\xc8\xde\xb6\x13" "\xe9\x4a\xa8\x5d\xeb\x86\xc2\x3a\x1c\x35\x0d\x36\xc3\x5a\xc1\x4c" "\xbb\x63\x87\xd8\xce\x17\xe5\x37\xf9\x1d\xe8\xb1\xf8\xc0\x51\xec" "\x65\xf8\x37\x70\x65\x81\x24\x2d\x21\x6c\x8c\x20\xf4\xb7\x1c\xd5" "\x80\xbe\x50\x6c\x3b\xf6\x5b\xf6\x76\x4a\x22\xb4\x04\x81\x0b\x58" "\x22\x2d\x07\xe0\xcc\x1a\x84\x5f\x30\x67\x92\xf8\xbb\x59\x0c\x82" "\xc2\x9b\x17\x1c\x4f\x50\xf7\xbd\x91\xf6\xb5\x87\x52\x22\x27\x02" "\xbc\x7e\xff\xc9\x4a\x9b\x9a\x43\xa9\x91\x91\x11\x61\x39\xe8\x3b" "\xcf\x8b\x6e\x07\x00\x00\x00\x34\x10\xad\x07\xa7\x81\x8f\x2d\x38" "\x5b\xdf\x94\xf1\x51\x32\x14\x91\xcf\x80\xbd\x6f\x5b\x06\xd4\x16" "\x57\x75\x01\x99\xa4\x84\x30\x69", 168)); r[4] = execute_syscall(__NR_setsockopt, r[2], 0x29ul, 0x39ul, 0x2000ef92ul, 0xa8ul, 0, 0, 0, 0); } int main() { setup_main_process(); int pid = do_sandbox_none(0, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; }