// https://syzkaller.appspot.com/bug?id=a133db4b32d89957481e21b5080f9edfa3bf4359 // 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 #include #include #include #include #include #include #include #include #include #ifndef __NR_io_pgetevents #define __NR_io_pgetevents 333 #endif static unsigned long long procid; static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _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(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } 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); } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) 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; } #define MAX_FDS 30 static long syz_open_dev(volatile long a0, volatile long a1, volatile 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; 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 void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void setup_binderfs() { if (mkdir("/dev/binderfs", 0777)) { } if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); setup_binderfs(); loop(); exit(1); } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { int iter = 0; DIR* dp = 0; retry: while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) { } dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exit(1); } exit(1); } struct dirent* ep = 0; 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); while (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) { } struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { if (unlink(filename) == 0) break; if (errno == EPERM) { int fd = open(filename, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno != EBUSY || i > 100) exit(1); if (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW)) exit(1); } } closedir(dp); for (int i = 0;; i++) { if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EPERM) { int fd = open(dir, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno == EBUSY) { if (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW)) exit(1); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exit(1); } } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); if (symlink("/dev/binderfs", "./binderfs")) { } } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); setup_test(); execute_one(); close_fds(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } remove_dir(cwdbuf); } } uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; syscall(__NR_sendmsg, -1, 0ul, 0x4000001ul); NONFAILING(memcpy((void*)0x20000000, "./file0\000", 8)); syscall(__NR_mkdir, 0x20000000ul, 0ul); NONFAILING(memcpy((void*)0x200000c0, "./file0\000", 8)); syscall(__NR_mount, 0x20000000ul, 0x200000c0ul, 0ul, 0x2001001ul, 0ul); syscall(__NR_socket, 0x10ul, 3ul, 0); NONFAILING(*(uint32_t*)0x20000700 = 1); NONFAILING(*(uint32_t*)0x20000704 = 0x80); NONFAILING(*(uint8_t*)0x20000708 = 0); NONFAILING(*(uint8_t*)0x20000709 = 0); NONFAILING(*(uint8_t*)0x2000070a = 0); NONFAILING(*(uint8_t*)0x2000070b = 0); NONFAILING(*(uint32_t*)0x2000070c = 0); NONFAILING(*(uint64_t*)0x20000710 = 6); NONFAILING(*(uint64_t*)0x20000718 = 0); NONFAILING(*(uint64_t*)0x20000720 = 0); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 0, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 1, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 2, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 4, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 5, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 6, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 7, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 8, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 9, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 10, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 11, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 12, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 13, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 14, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 15, 2)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 17, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 18, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 19, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 20, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 21, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 22, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 23, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 24, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 25, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 26, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 27, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 28, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 29, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 30, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 31, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 32, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 33, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 34, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 35, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 36, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 37, 1)); NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000728, 0, 38, 26)); NONFAILING(*(uint32_t*)0x20000730 = 0); NONFAILING(*(uint32_t*)0x20000734 = 0); NONFAILING(*(uint64_t*)0x20000738 = 2); NONFAILING(*(uint64_t*)0x20000740 = 0); NONFAILING(*(uint64_t*)0x20000748 = 2); NONFAILING(*(uint64_t*)0x20000750 = 0); NONFAILING(*(uint32_t*)0x20000758 = 0); NONFAILING(*(uint32_t*)0x2000075c = 2); NONFAILING(*(uint64_t*)0x20000760 = 3); NONFAILING(*(uint32_t*)0x20000768 = 0xfffffffd); NONFAILING(*(uint16_t*)0x2000076c = 0); NONFAILING(*(uint16_t*)0x2000076e = 0); NONFAILING(*(uint32_t*)0x20000770 = 0); NONFAILING(*(uint32_t*)0x20000774 = 0); NONFAILING(*(uint64_t*)0x20000778 = 0); res = syscall(__NR_perf_event_open, 0x20000700ul, 0, -1ul, -1, 0ul); if (res != -1) r[0] = res; syscall(__NR_ioctl, -1, 0x8040451b, 0ul); NONFAILING(memcpy((void*)0x20000300, "./file0\000", 8)); NONFAILING(memcpy((void*)0x20000180, "./file0\000", 8)); syscall(__NR_pivot_root, 0x20000300ul, 0x20000180ul); res = syscall(__NR_socket, 0x10ul, 3ul, 0); if (res != -1) r[1] = res; res = syscall(__NR_socket, 0xaul, 3ul, 0x3a); if (res != -1) r[2] = res; NONFAILING(*(uint32_t*)0x20000140 = 0x6e); syscall(__NR_getpeername, -1, 0x20000200ul, 0x20000140ul); syscall(__NR_io_cancel, 0ul, 0ul, 0x200002c0ul); NONFAILING( memcpy((void*)0x20000340, "\xa8\xb8\xaa\xe1\xd4\x2e\x4d\x92\x70\x10\x4f\x01\x9b\xe3\x3d\x35" "\xd7\x49\xab\x2f\x18\x7e\x43\x03\x42\xe3\x75\xa4\x5d\xf4\x01\x05" "\x00\x29\x03\x17\xbc\xc7\xe9\x0a\x58\x51\xa3\xc2\x89\x45\x58\x91" "\x0c\xbe\x6d\x0a\x2c\xa7\x3d\xac\x6c\x1f\x87\x5d\xd7\xc8\x3e\x4e" "\x3a\xae\x1e\x03\x70\x47\x4f\xc8\x46\x75\xcd\x91\xa2\xdc\x85\xd3" "\x28\x9d\x75\x13\x93\xd0\x72\xcd\x8c\xf1\xe4\x24\xba\xdf\x8b\xdd" "\x68\x12\x29\x90\x46\xc8\x10\xbd\xff\x07\x00\x04\x00\x00\x00", 111)); syscall(__NR_fremovexattr, r[0], 0x20000340ul); res = -1; NONFAILING(res = syz_open_dev(0xc, 0xb4, 0xa9b)); if (res != -1) r[3] = res; NONFAILING(*(uint64_t*)0x20000080 = 2); syscall(__NR_fcntl, r[3], 0x40cul, 0x20000080ul); syscall(__NR_ioctl, -1, 0x8933, 0ul); NONFAILING(*(uint16_t*)0x20000100 = 0xa); NONFAILING(*(uint16_t*)0x20000102 = htobe16(0)); NONFAILING(*(uint32_t*)0x20000104 = htobe32(0)); NONFAILING(memset((void*)0x20000108, 0, 16)); NONFAILING(*(uint32_t*)0x20000118 = 0); syscall(__NR_connect, r[2], 0x20000100ul, 0x1cul); NONFAILING(*(uint64_t*)0x200003c0 = 0x20000280); NONFAILING(*(uint64_t*)0x20000280 = 3); NONFAILING(*(uint64_t*)0x200003c8 = 8); syscall(__NR_io_pgetevents, 0ul, 0x89a2ul, 1ul, 0x200001c0ul, 0ul, 0x200003c0ul); NONFAILING(*(uint64_t*)0x20000540 = 0x20000040); NONFAILING( memcpy((void*)0x20000040, "\x39\x00\x00\x00\x13\x00\x03\x47\x00\xbb\x65\xe1\xc3\xe4\xff\xff" "\x06\x00\x00\x00\x01\x00\x00\x00\x45\x00\x00\x00\x25\x00\x00\x00" "\x19\x00\x04\x00\x04\x00\x00\x00\x07\xfd\x17\xe5\xff\xff\x06\x06" "\x04\x00\x00\x00\x00\x00\x00\x00\x00", 57)); NONFAILING(*(uint64_t*)0x20000548 = 0x39); syscall(__NR_writev, r[1], 0x20000540ul, 1ul); } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); install_segv_handler(); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { use_temporary_dir(); do_sandbox_none(); } } sleep(1000000); return 0; }