// https://syzkaller.appspot.com/bug?id=7022420cc54310220ebad2da89e499bdb1f0f5e8 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { 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)) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { 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); 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); \ } static void use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } static long syz_open_dev(long a0, long a1, long a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; NONFAILING(strncpy(buf, (char*)a0, sizeof(buf) - 1)); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } static int inject_fault(int nth) { int fd; char buf[16]; fd = open("/proc/thread-self/fail-nth", O_RDWR); if (fd == -1) exit(1); sprintf(buf, "%d", nth + 1); if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) exit(1); return fd; } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); install_segv_handler(); use_temporary_dir(); long res = 0; res = syscall(__NR_socket, 0xa, 0x803, 3); if (res != -1) r[0] = res; syscall(__NR_ioctl, r[0], 0x1000008912, 0); syscall(__NR_perf_event_open, 0, 0, 0, -1, 0); NONFAILING(memcpy((void*)0x20000140, "/dev/dsp#", 10)); res = syz_open_dev(0x20000140, 1, 2); if (res != -1) r[1] = res; NONFAILING(*(uint64_t*)0x20000040 = 0); syscall(__NR_ioctl, r[1], 0x800000c004500a, 0x20000040); NONFAILING(*(uint32_t*)0x200000c0 = 0xffffff71); NONFAILING(*(uint32_t*)0x200000c4 = 5); NONFAILING(*(uint64_t*)0x200000c8 = 0x100000000000d00); NONFAILING(*(uint64_t*)0x200000d0 = 0x186a0); NONFAILING(*(uint64_t*)0x200000d8 = 0); NONFAILING(*(uint64_t*)0x200000e0 = 0); NONFAILING(*(uint32_t*)0x200000e8 = 0); NONFAILING(*(uint32_t*)0x200000ec = 0); write_file("/sys/kernel/debug/failslab/ignore-gfp-wait", "N"); write_file("/sys/kernel/debug/fail_futex/ignore-private", "N"); inject_fault(6); syscall(__NR_write, r[1], 0x200000c0, 0x56da83a0); return 0; }