// https://syzkaller.appspot.com/bug?id=4acb2aa300d1adc7695b387fb986b9ef00680908 // 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 #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; } 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)) { } if (symlink("/dev/binderfs", "./binderfs")) { } } 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 = 0; 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)) { } setup_binderfs(); loop(); exit(1); } uint64_t r[3] = {0xffffffffffffffff, 0x0, 0xffffffffffffffff}; void loop(void) { intptr_t res = 0; res = syscall(__NR_socket, 0x10ul, 0x803ul, 0); if (res != -1) r[0] = res; *(uint64_t*)0x20000280 = 0; *(uint32_t*)0x20000288 = 0; *(uint64_t*)0x20000290 = 0x20000240; *(uint64_t*)0x20000240 = 0; *(uint64_t*)0x20000248 = 0; *(uint64_t*)0x20000298 = 1; *(uint64_t*)0x200002a0 = 0; *(uint64_t*)0x200002a8 = 0; *(uint32_t*)0x200002b0 = 0; syscall(__NR_sendmsg, r[0], 0x20000280ul, 0ul); *(uint32_t*)0x20000440 = 0x14; res = syscall(__NR_getsockname, r[0], 0x20000200ul, 0x20000440ul); if (res != -1) r[1] = *(uint32_t*)0x20000204; *(uint64_t*)0x200002c0 = 0; *(uint32_t*)0x200002c8 = 0; *(uint64_t*)0x200002d0 = 0x200000c0; *(uint64_t*)0x200000c0 = 0x20000380; memcpy((void*)0x20000380, "\x50\x00\x00\x00\x24\x00\x0b\x1d\x00\x08\x00\x80\x00\x00\x00\x00\x00" "\x00\x00\x00", 20); *(uint32_t*)0x20000394 = r[1]; memcpy((void*)0x20000398, "\x00\x00\x00\x00\xff\xff\xff\xff\x00\x00\x03\x00\x0d\x00\x01\x00\x66" "\x71\x5f\x63\x6f\x64\x65\x6c", 24); *(uint64_t*)0x200000c8 = 0x50; *(uint64_t*)0x200002d8 = 1; *(uint64_t*)0x200002e0 = 0; *(uint64_t*)0x200002e8 = 0; *(uint32_t*)0x200002f0 = 0; syscall(__NR_sendmsg, -1, 0x200002c0ul, 0ul); *(uint64_t*)0x20000300 = 0; *(uint32_t*)0x20000308 = 0; *(uint64_t*)0x20000310 = 0x20000180; *(uint64_t*)0x20000180 = 0x200005c0; *(uint32_t*)0x200005c0 = 0x70; *(uint16_t*)0x200005c4 = 0x2c; *(uint16_t*)0x200005c6 = 0xd27; *(uint32_t*)0x200005c8 = 0; *(uint32_t*)0x200005cc = 0; *(uint8_t*)0x200005d0 = 0; *(uint8_t*)0x200005d1 = 0; *(uint16_t*)0x200005d2 = 0; *(uint32_t*)0x200005d4 = r[1]; *(uint16_t*)0x200005d8 = 0; *(uint16_t*)0x200005da = 0; *(uint16_t*)0x200005dc = 0; *(uint16_t*)0x200005de = 0; *(uint16_t*)0x200005e0 = 0xc; *(uint16_t*)0x200005e2 = 0; *(uint16_t*)0x200005e4 = 9; *(uint16_t*)0x200005e6 = 1; memcpy((void*)0x200005e8, "flow\000", 5); *(uint16_t*)0x200005f0 = 0x40; *(uint16_t*)0x200005f2 = 2; *(uint16_t*)0x200005f4 = 0x3c; STORE_BY_BITMASK(uint16_t, , 0x200005f6, 0xb, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200005f7, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200005f7, 1, 7, 1); *(uint16_t*)0x200005f8 = 8; *(uint16_t*)0x200005fa = 1; *(uint16_t*)0x200005fc = 9; *(uint16_t*)0x200005fe = 0; *(uint16_t*)0x20000600 = 0x30; STORE_BY_BITMASK(uint16_t, , 0x20000602, 2, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x20000603, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x20000603, 1, 7, 1); *(uint16_t*)0x20000604 = 0x2c; STORE_BY_BITMASK(uint16_t, , 0x20000606, 1, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x20000607, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x20000607, 0, 7, 1); *(uint16_t*)0x20000608 = 0; *(uint16_t*)0x2000060a = 9; *(uint16_t*)0x2000060c = 0; *(uint16_t*)0x2000060e = 0; *(uint16_t*)0x20000610 = 5; *(uint16_t*)0x20000612 = 4; *(uint8_t*)0x20000614 = 0xcc; *(uint16_t*)0x20000618 = 4; *(uint16_t*)0x2000061a = 5; *(uint16_t*)0x2000061c = 0xb; *(uint16_t*)0x2000061e = 2; memcpy((void*)0x20000620, "policy\000", 7); *(uint16_t*)0x20000628 = 8; *(uint16_t*)0x2000062a = 1; *(uint32_t*)0x2000062c = 0; *(uint64_t*)0x20000188 = 0x70; *(uint64_t*)0x20000318 = 1; *(uint64_t*)0x20000320 = 0; *(uint64_t*)0x20000328 = 0; *(uint32_t*)0x20000330 = 0; syscall(__NR_sendmsg, -1, 0x20000300ul, 0ul); res = syscall(__NR_socket, 0x10ul, 3ul, 0); if (res != -1) r[2] = res; syscall(__NR_sendmmsg, r[2], 0x200002c0ul, 0x40000000000009ful, 0ul); } 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); do_sandbox_none(); return 0; }