// https://syzkaller.appspot.com/bug?id=df466e1151a7e45dd880d8c7033f1ad48acebfb4 // 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 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; } #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 void setup_gadgetfs(); static void setup_binderfs(); static void setup_fusectl(); static void sandbox_common_mount_tmpfs(void) { write_file("/proc/sys/fs/mount-max", "100000"); if (mkdir("./syz-tmp", 0777)) exit(1); if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) exit(1); if (mkdir("./syz-tmp/newroot", 0777)) exit(1); if (mkdir("./syz-tmp/newroot/dev", 0700)) exit(1); unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; if (mount("/dev", "./syz-tmp/newroot/dev", NULL, bind_mount_flags, NULL)) exit(1); if (mkdir("./syz-tmp/newroot/proc", 0700)) exit(1); if (mount("syz-proc", "./syz-tmp/newroot/proc", "proc", 0, NULL)) exit(1); if (mkdir("./syz-tmp/newroot/selinux", 0700)) exit(1); const char* selinux_path = "./syz-tmp/newroot/selinux"; if (mount("/selinux", selinux_path, NULL, bind_mount_flags, NULL)) { if (errno != ENOENT) exit(1); if (mount("/sys/fs/selinux", selinux_path, NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); } if (mkdir("./syz-tmp/newroot/sys", 0700)) exit(1); if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL)) exit(1); if (mount("/sys/kernel/debug", "./syz-tmp/newroot/sys/kernel/debug", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mount("/sys/fs/smackfs", "./syz-tmp/newroot/sys/fs/smackfs", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mount("/proc/sys/fs/binfmt_misc", "./syz-tmp/newroot/proc/sys/fs/binfmt_misc", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mkdir("./syz-tmp/newroot/syz-inputs", 0700)) exit(1); if (mount("/syz-inputs", "./syz-tmp/newroot/syz-inputs", NULL, bind_mount_flags | MS_RDONLY, NULL) && errno != ENOENT) exit(1); if (mkdir("./syz-tmp/pivot", 0777)) exit(1); if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { if (chdir("./syz-tmp")) exit(1); } else { if (chdir("/")) exit(1); if (umount2("./pivot", MNT_DETACH)) exit(1); } if (chroot("./newroot")) exit(1); if (chdir("/")) exit(1); setup_gadgetfs(); setup_binderfs(); setup_fusectl(); } static void setup_gadgetfs() { if (mkdir("/dev/gadgetfs", 0777)) { } if (mount("gadgetfs", "/dev/gadgetfs", "gadgetfs", 0, NULL)) { } } static void setup_fusectl() { 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); if (getppid() == 1) exit(1); 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); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); sandbox_common_mount_tmpfs(); loop(); 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"); } 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++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); close_fds(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // socket$nl_route arguments: [ // domain: const = 0x10 (8 bytes) // type: const = 0x3 (8 bytes) // proto: const = 0x0 (4 bytes) // ] // returns sock_nl_route res = syscall(__NR_socket, /*domain=*/0x10ul, /*type=*/3ul, /*proto=*/0); if (res != -1) r[0] = res; // socket$inet_udplite arguments: [ // domain: const = 0x2 (8 bytes) // type: const = 0x2 (8 bytes) // proto: const = 0x88 (4 bytes) // ] // returns sock_udp res = syscall(__NR_socket, /*domain=*/2ul, /*type=*/2ul, /*proto=*/0x88); if (res != -1) r[1] = res; // ioctl$sock_SIOCGIFINDEX arguments: [ // fd: sock (resource) // cmd: const = 0x8933 (4 bytes) // arg: ptr[out, ifreq_dev_t[devnames, ifindex]] { // ifreq_dev_t[devnames, ifindex] { // ifr_ifrn: buffer: {62 6f 6e 64 30 00 00 00 00 00 00 00 00 00 00 00} // (length 0x10) elem: ifindex (resource) pad = 0x0 (20 bytes) // } // } // ] memcpy((void*)0x200000000000, "bond0\000\000\000\000\000\000\000\000\000\000\000", 16); res = syscall(__NR_ioctl, /*fd=*/r[1], /*cmd=*/0x8933, /*arg=*/0x200000000000ul); if (res != -1) r[2] = *(uint32_t*)0x200000000010; // sendmsg$nl_route arguments: [ // fd: sock_nl_route (resource) // msg: ptr[in, msghdr_netlink[netlink_msg_route]] { // msghdr_netlink[netlink_msg_route] { // addr: nil // addrlen: len = 0x0 (4 bytes) // pad = 0x0 (4 bytes) // vec: ptr[in, iovec[in, netlink_msg_route]] { // iovec[in, netlink_msg_route] { // addr: ptr[in, netlink_msg_route] { // union netlink_msg_route { // newlink: netlink_msg_t[const[RTM_NEWLINK, int16], // ifinfomsg[AF_UNSPEC], ifla_policy] { // len: len = 0x4c (4 bytes) // type: const = 0x10 (2 bytes) // flags: netlink_msg_flags = 0x49920d862a92153b (2 bytes) // seq: int32 = 0x800 (4 bytes) // pid: int32 = 0x0 (4 bytes) // payload: ifinfomsg[AF_UNSPEC] { // ifi_family: const = 0x0 (1 bytes) // __ifi_pad: const = 0x0 (1 bytes) // ifi_type: const = 0x0 (2 bytes) // ifi_index: ifindex (resource) // ifi_flags: net_device_flags = 0x0 (4 bytes) // ifi_change: net_device_flags = 0x1b400 (4 bytes) // } // attrs: array[ifla_policy] { // union ifla_policy { // IFLA_LINKINFO: nlattr_tt[const[IFLA_LINKINFO, // int16:14], 0, 1, ifla_info_policy] { // nla_len: offsetof = 0x24 (2 bytes) // nla_type: const = 0x12 (1 bytes) // NLA_F_NET_BYTEORDER: const = 0x0 (0 bytes) // NLA_F_NESTED: const = 0x1 (1 bytes) // payload: union ifla_info_policy { // bond: ifla_info_policy$t["bond", IFLA_INFO_DATA, // array[bond_policy]] { // IFLA_INFO_KIND: nlattr_t[const[IFLA_INFO_KIND, // int16], string["bond"]] { // nla_len: offsetof = 0x9 (2 bytes) // nla_type: const = 0x1 (2 bytes) // payload: buffer: {62 6f 6e 64 00} (length 0x5) // size: buffer: {} (length 0x0) // pad = 0x0 (3 bytes) // } // IFLA_INFO_DATA: nlattr_tt[const[IFLA_INFO_DATA, // int16:14], 0, 1, array[bond_policy]] { // nla_len: offsetof = 0x14 (2 bytes) // nla_type: const = 0x2 (1 bytes) // NLA_F_NET_BYTEORDER: const = 0x0 (0 bytes) // NLA_F_NESTED: const = 0x1 (1 bytes) // payload: array[bond_policy] { // union bond_policy { // IFLA_BOND_MODE: // nlattr_t[const[IFLA_BOND_MODE, int16], // int8[0:6]] { // nla_len: offsetof = 0x5 (2 bytes) // nla_type: const = 0x1 (2 bytes) // payload: int8 = 0x6 (1 bytes) // size: buffer: {} (length 0x0) // pad = 0x0 (3 bytes) // } // } // union bond_policy { // IFLA_BOND_MIIMON: // nlattr_t[const[IFLA_BOND_MIIMON, int16], // int32] { // nla_len: offsetof = 0x8 (2 bytes) // nla_type: const = 0x3 (2 bytes) // payload: int32 = 0x0 (4 bytes) // size: buffer: {} (length 0x0) // } // } // } // size: buffer: {} (length 0x0) // } // } // } // size: buffer: {} (length 0x0) // } // } // union ifla_policy { // IFLA_MASTER: nlattr_t[const[IFLA_MASTER, int16], // ifindex] { // nla_len: offsetof = 0x8 (2 bytes) // nla_type: const = 0xa (2 bytes) // payload: ifindex (resource) // size: buffer: {} (length 0x0) // } // } // } // } // } // } // len: len = 0x4c (8 bytes) // } // } // vlen: const = 0x1 (8 bytes) // ctrl: const = 0x0 (8 bytes) // ctrllen: const = 0x0 (8 bytes) // f: send_flags = 0x0 (4 bytes) // pad = 0x0 (4 bytes) // } // } // f: send_flags = 0x0 (8 bytes) // ] *(uint64_t*)0x200000000000 = 0; *(uint32_t*)0x200000000008 = 0; *(uint64_t*)0x200000000010 = 0x200000000040; *(uint64_t*)0x200000000040 = 0x200000001400; *(uint32_t*)0x200000001400 = 0x4c; *(uint16_t*)0x200000001404 = 0x10; *(uint16_t*)0x200000001406 = 0x153b; *(uint32_t*)0x200000001408 = 0x800; *(uint32_t*)0x20000000140c = 0; *(uint8_t*)0x200000001410 = 0; *(uint8_t*)0x200000001411 = 0; *(uint16_t*)0x200000001412 = 0; *(uint32_t*)0x200000001414 = 0; *(uint32_t*)0x200000001418 = 0; *(uint32_t*)0x20000000141c = 0x1b400; *(uint16_t*)0x200000001420 = 0x24; STORE_BY_BITMASK(uint16_t, , 0x200000001422, 0x12, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000001423, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000001423, 1, 7, 1); *(uint16_t*)0x200000001424 = 9; *(uint16_t*)0x200000001426 = 1; memcpy((void*)0x200000001428, "bond\000", 5); *(uint16_t*)0x200000001430 = 0x14; STORE_BY_BITMASK(uint16_t, , 0x200000001432, 2, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000001433, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000001433, 1, 7, 1); *(uint16_t*)0x200000001434 = 5; *(uint16_t*)0x200000001436 = 1; *(uint8_t*)0x200000001438 = 6; *(uint16_t*)0x20000000143c = 8; *(uint16_t*)0x20000000143e = 3; *(uint32_t*)0x200000001440 = 0; *(uint16_t*)0x200000001444 = 8; *(uint16_t*)0x200000001446 = 0xa; *(uint32_t*)0x200000001448 = r[2]; *(uint64_t*)0x200000000048 = 0x4c; *(uint64_t*)0x200000000018 = 1; *(uint64_t*)0x200000000020 = 0; *(uint64_t*)0x200000000028 = 0; *(uint32_t*)0x200000000030 = 0; syscall(__NR_sendmsg, /*fd=*/r[0], /*msg=*/0x200000000000ul, /*f=*/0ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; do_sandbox_none(); return 0; }