// https://syzkaller.appspot.com/bug?id=5fae93fe246c95eadcb5a317ff3806492a3f9492 // 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 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 = 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); } uint64_t r[4] = {0xffffffffffffffff, 0x0, 0xffffffffffffffff, 0xffffffffffffffff}; void loop(void) { intptr_t res = 0; res = syscall(__NR_socket, 0x10ul, 0x803ul, 0); if (res != -1) r[0] = res; *(uint64_t*)0x20000900 = 0; *(uint32_t*)0x20000908 = 0; *(uint64_t*)0x20000910 = 0x200008c0; *(uint64_t*)0x200008c0 = 0x20000880; *(uint32_t*)0x20000880 = 0x10; *(uint16_t*)0x20000884 = 0x3f2; *(uint16_t*)0x20000886 = 0; *(uint32_t*)0x20000888 = 0; *(uint32_t*)0x2000088c = 0; *(uint64_t*)0x200008c8 = 0x10; *(uint64_t*)0x20000918 = 1; *(uint64_t*)0x20000920 = 0; *(uint64_t*)0x20000928 = 0; *(uint32_t*)0x20000930 = 0; syscall(__NR_sendmsg, r[0], 0x20000900ul, 0ul); *(uint64_t*)0x20000280 = 0; *(uint32_t*)0x20000288 = 0; *(uint64_t*)0x20000290 = 0x20000180; *(uint64_t*)0x20000180 = 0; *(uint64_t*)0x20000188 = 0; *(uint64_t*)0x20000298 = 1; *(uint64_t*)0x200002a0 = 0; *(uint64_t*)0x200002a8 = 0; *(uint32_t*)0x200002b0 = 0; syscall(__NR_sendmsg, -1, 0x20000280ul, 0ul); *(uint32_t*)0x20000100 = 0x14; res = syscall(__NR_getsockname, r[0], 0x200000c0ul, 0x20000100ul); if (res != -1) r[1] = *(uint32_t*)0x200000c4; *(uint64_t*)0x20000240 = 0; *(uint32_t*)0x20000248 = 0; *(uint64_t*)0x20000250 = 0x20000140; *(uint64_t*)0x20000140 = 0x20000300; memcpy((void*)0x20000300, "\x38\x00\x00\x00\x24\x00\x07\x05\x00\x00\x00\x40\x13\xa2\xa3\x00\x05" "\x00\x00\x00", 20); *(uint32_t*)0x20000314 = r[1]; memcpy((void*)0x20000318, "\x00\x00\x00\x00\xff\xff\xff\xff\x00\x00\x00\x00\x09\x00\x01\x00\x68" "\x66\x73\x63\x00\x00\x00\x00\x08\x00\x02", 27); *(uint64_t*)0x20000148 = 0x38; *(uint64_t*)0x20000258 = 1; *(uint64_t*)0x20000260 = 0; *(uint64_t*)0x20000268 = 0; *(uint32_t*)0x20000270 = 0; syscall(__NR_sendmsg, -1, 0x20000240ul, 0ul); *(uint64_t*)0x20000200 = 0; *(uint32_t*)0x20000208 = 0; *(uint64_t*)0x20000210 = 0x20000180; *(uint64_t*)0x20000180 = 0x200003c0; *(uint32_t*)0x200003c0 = 0x34; *(uint16_t*)0x200003c4 = 0x2c; *(uint16_t*)0x200003c6 = 0xd27; *(uint32_t*)0x200003c8 = 0; *(uint32_t*)0x200003cc = 0; *(uint8_t*)0x200003d0 = 0; *(uint8_t*)0x200003d1 = 0; *(uint16_t*)0x200003d2 = 0; *(uint32_t*)0x200003d4 = r[1]; *(uint16_t*)0x200003d8 = 0; *(uint16_t*)0x200003da = 3; *(uint16_t*)0x200003dc = 0; *(uint16_t*)0x200003de = 0; *(uint16_t*)0x200003e0 = 0xfff1; *(uint16_t*)0x200003e2 = 0xfff2; *(uint16_t*)0x200003e4 = 0xc; *(uint16_t*)0x200003e6 = 1; memcpy((void*)0x200003e8, "tcindex\000", 8); *(uint16_t*)0x200003f0 = 4; *(uint16_t*)0x200003f2 = 2; *(uint64_t*)0x20000188 = 0x34; *(uint64_t*)0x20000218 = 1; *(uint64_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0; *(uint32_t*)0x20000230 = 0; syscall(__NR_sendmsg, -1, 0x20000200ul, 0ul); res = syscall(__NR_socket, 0x1000000010ul, 0x80002ul, 0); if (res != -1) r[2] = res; syscall(__NR_sendmmsg, r[2], 0x20000200ul, 0x10efe10675dec16ul, 0ul); res = syscall(__NR_socket, 0x1000000010ul, 0x80002ul, 0); if (res != -1) r[3] = res; syscall(__NR_sendmmsg, r[3], 0x20000200ul, 0x4924924924926d3ul, 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; }