// https://syzkaller.appspot.com/bug?id=00b395ed1c95e10c5623e185b2e3d5912cd72f63 // 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 #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 uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } 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 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; fd = open("/proc/thread-self/fail-nth", O_RDWR); if (fd == -1) exit(1); char buf[16]; sprintf(buf, "%d", nth + 1); if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) exit(1); return fd; } static void setup_fault() { static struct { const char* file; const char* val; bool fatal; } files[] = { {"/sys/kernel/debug/failslab/ignore-gfp-wait", "N", true}, {"/sys/kernel/debug/fail_futex/ignore-private", "N", false}, {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem", "N", false}, {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait", "N", false}, {"/sys/kernel/debug/fail_page_alloc/min-order", "0", false}, }; unsigned i; for (i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].file, files[i].val)) { if (files[i].fatal) exit(1); } } } #define KMEMLEAK_FILE "/sys/kernel/debug/kmemleak" static void setup_leak() { if (!write_file(KMEMLEAK_FILE, "scan")) exit(1); sleep(5); if (!write_file(KMEMLEAK_FILE, "scan")) exit(1); if (!write_file(KMEMLEAK_FILE, "clear")) exit(1); } static void check_leaks(void) { int fd = open(KMEMLEAK_FILE, O_RDWR); if (fd == -1) exit(1); uint64_t start = current_time_ms(); if (write(fd, "scan", 4) != 4) exit(1); sleep(1); while (current_time_ms() - start < 4 * 1000) sleep(1); if (write(fd, "scan", 4) != 4) exit(1); static char buf[128 << 10]; ssize_t n = read(fd, buf, sizeof(buf) - 1); if (n < 0) exit(1); int nleaks = 0; if (n != 0) { sleep(1); if (write(fd, "scan", 4) != 4) exit(1); if (lseek(fd, 0, SEEK_SET) < 0) exit(1); n = read(fd, buf, sizeof(buf) - 1); if (n < 0) exit(1); buf[n] = 0; char* pos = buf; char* end = buf + n; while (pos < end) { char* next = strstr(pos + 1, "unreferenced object"); if (!next) next = end; char prev = *next; *next = 0; fprintf(stderr, "BUG: memory leak\n%s\n", pos); *next = prev; pos = next; nleaks++; } } if (write(fd, "clear", 5) != 5) exit(1); close(fd); if (nleaks) exit(1); } uint64_t r[1] = {0xffffffffffffffff}; int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); setup_leak(); setup_fault(); install_segv_handler(); use_temporary_dir(); intptr_t res = 0; res = syscall(__NR_socket, 0x10, 3, 0); if (res != -1) r[0] = res; syscall(__NR_socketpair, 1, 2, 0, 0); syscall(__NR_ioctl, -1, 0x8912, 0x400200); NONFAILING(*(uint64_t*)0x20000580 = 0); NONFAILING(*(uint32_t*)0x20000588 = 0xc8); NONFAILING(*(uint64_t*)0x20000590 = 0x20000000); NONFAILING(*(uint64_t*)0x20000000 = 0x20000140); NONFAILING(*(uint32_t*)0x20000140 = 0x50); NONFAILING(*(uint16_t*)0x20000144 = 0x10); NONFAILING(*(uint16_t*)0x20000146 = 0x705); NONFAILING(*(uint32_t*)0x20000148 = 0); NONFAILING(*(uint32_t*)0x2000014c = 0); NONFAILING(*(uint8_t*)0x20000150 = 0); NONFAILING(*(uint8_t*)0x20000151 = 0); NONFAILING(*(uint16_t*)0x20000152 = 0); NONFAILING(*(uint32_t*)0x20000154 = 0); NONFAILING(*(uint32_t*)0x20000158 = 0); NONFAILING(*(uint32_t*)0x2000015c = 0); NONFAILING(*(uint16_t*)0x20000160 = 8); NONFAILING(*(uint16_t*)0x20000162 = 0xd); NONFAILING(*(uint8_t*)0x20000164 = 0); NONFAILING(*(uint16_t*)0x20000168 = 0x28); NONFAILING(*(uint16_t*)0x2000016a = 0x12); NONFAILING(*(uint16_t*)0x2000016c = 0xc); NONFAILING(*(uint16_t*)0x2000016e = 1); NONFAILING(memcpy((void*)0x20000170, "veth\000", 5)); NONFAILING(*(uint16_t*)0x20000178 = 0x18); NONFAILING(*(uint16_t*)0x2000017a = 2); NONFAILING(*(uint16_t*)0x2000017c = 0x14); NONFAILING(*(uint16_t*)0x2000017e = 1); NONFAILING(*(uint8_t*)0x20000180 = 0); NONFAILING(*(uint8_t*)0x20000181 = 0); NONFAILING(*(uint16_t*)0x20000182 = 0); NONFAILING(*(uint32_t*)0x20000184 = 0); NONFAILING(*(uint32_t*)0x20000188 = 0); NONFAILING(*(uint32_t*)0x2000018c = 0); NONFAILING(*(uint64_t*)0x20000008 = 0x50); NONFAILING(*(uint64_t*)0x20000598 = 1); NONFAILING(*(uint64_t*)0x200005a0 = 0); NONFAILING(*(uint64_t*)0x200005a8 = 0); NONFAILING(*(uint32_t*)0x200005b0 = 0); inject_fault(92); syscall(__NR_sendmsg, r[0], 0x20000580, 0); check_leaks(); return 0; }