// https://syzkaller.appspot.com/bug?id=29a05f558dd8f68f2f9216c6b007a72e1cb6d70d // 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 #include #ifndef __NR_bpf #define __NR_bpf 321 #endif 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); } 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 #define USB_MAX_IFACE_NUM 4 #define USB_MAX_EP_NUM 32 #define USB_MAX_FDS 6 struct usb_endpoint_index { struct usb_endpoint_descriptor desc; int handle; }; struct usb_iface_index { struct usb_interface_descriptor* iface; uint8_t bInterfaceNumber; uint8_t bAlternateSetting; uint8_t bInterfaceClass; struct usb_endpoint_index eps[USB_MAX_EP_NUM]; int eps_num; }; struct usb_device_index { struct usb_device_descriptor* dev; struct usb_config_descriptor* config; uint8_t bDeviceClass; uint8_t bMaxPower; int config_length; struct usb_iface_index ifaces[USB_MAX_IFACE_NUM]; int ifaces_num; int iface_cur; }; struct usb_info { int fd; struct usb_device_index index; }; static struct usb_info usb_devices[USB_MAX_FDS]; static struct usb_device_index* lookup_usb_index(int fd) { for (int i = 0; i < USB_MAX_FDS; i++) { if (__atomic_load_n(&usb_devices[i].fd, __ATOMIC_ACQUIRE) == fd) return &usb_devices[i].index; } return NULL; } struct vusb_connect_string_descriptor { uint32_t len; char* str; } __attribute__((packed)); struct vusb_connect_descriptors { uint32_t qual_len; char* qual; uint32_t bos_len; char* bos; uint32_t strs_len; struct vusb_connect_string_descriptor strs[0]; } __attribute__((packed)); typedef bool (*lookup_connect_out_response_t)( int fd, const struct vusb_connect_descriptors* descs, const struct usb_ctrlrequest* ctrl, bool* done); #define UDC_NAME_LENGTH_MAX 128 struct usb_raw_init { __u8 driver_name[UDC_NAME_LENGTH_MAX]; __u8 device_name[UDC_NAME_LENGTH_MAX]; __u8 speed; }; enum usb_raw_event_type { USB_RAW_EVENT_INVALID = 0, USB_RAW_EVENT_CONNECT = 1, USB_RAW_EVENT_CONTROL = 2, }; struct usb_raw_event { __u32 type; __u32 length; __u8 data[0]; }; struct usb_raw_ep_io { __u16 ep; __u16 flags; __u32 length; __u8 data[0]; }; #define USB_RAW_EPS_NUM_MAX 30 #define USB_RAW_EP_NAME_MAX 16 #define USB_RAW_EP_ADDR_ANY 0xff struct usb_raw_ep_caps { __u32 type_control : 1; __u32 type_iso : 1; __u32 type_bulk : 1; __u32 type_int : 1; __u32 dir_in : 1; __u32 dir_out : 1; }; struct usb_raw_ep_limits { __u16 maxpacket_limit; __u16 max_streams; __u32 reserved; }; struct usb_raw_ep_info { __u8 name[USB_RAW_EP_NAME_MAX]; __u32 addr; struct usb_raw_ep_caps caps; struct usb_raw_ep_limits limits; }; struct usb_raw_eps_info { struct usb_raw_ep_info eps[USB_RAW_EPS_NUM_MAX]; }; #define USB_RAW_IOCTL_INIT _IOW('U', 0, struct usb_raw_init) #define USB_RAW_IOCTL_RUN _IO('U', 1) #define USB_RAW_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_raw_event) #define USB_RAW_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_raw_ep_io) #define USB_RAW_IOCTL_EP0_READ _IOWR('U', 4, struct usb_raw_ep_io) #define USB_RAW_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor) #define USB_RAW_IOCTL_EP_DISABLE _IOW('U', 6, __u32) #define USB_RAW_IOCTL_EP_WRITE _IOW('U', 7, struct usb_raw_ep_io) #define USB_RAW_IOCTL_EP_READ _IOWR('U', 8, struct usb_raw_ep_io) #define USB_RAW_IOCTL_CONFIGURE _IO('U', 9) #define USB_RAW_IOCTL_VBUS_DRAW _IOW('U', 10, __u32) #define USB_RAW_IOCTL_EPS_INFO _IOR('U', 11, struct usb_raw_eps_info) #define USB_RAW_IOCTL_EP0_STALL _IO('U', 12) #define USB_RAW_IOCTL_EP_SET_HALT _IOW('U', 13, __u32) #define USB_RAW_IOCTL_EP_CLEAR_HALT _IOW('U', 14, __u32) #define USB_RAW_IOCTL_EP_SET_WEDGE _IOW('U', 15, __u32) static int usb_raw_ep_read(int fd, struct usb_raw_ep_io* io) { return ioctl(fd, USB_RAW_IOCTL_EP_READ, io); } static int lookup_endpoint(int fd, uint8_t bEndpointAddress) { struct usb_device_index* index = lookup_usb_index(fd); if (!index) return -1; if (index->iface_cur < 0) return -1; for (int ep = 0; ep < index->ifaces[index->iface_cur].eps_num; ep++) if (index->ifaces[index->iface_cur].eps[ep].desc.bEndpointAddress == bEndpointAddress) return index->ifaces[index->iface_cur].eps[ep].handle; return -1; } #define USB_MAX_PACKET_SIZE 4096 struct usb_raw_control_event { struct usb_raw_event inner; struct usb_ctrlrequest ctrl; char data[USB_MAX_PACKET_SIZE]; }; struct usb_raw_ep_io_data { struct usb_raw_ep_io inner; char data[USB_MAX_PACKET_SIZE]; }; static volatile long syz_usb_ep_read(volatile long a0, volatile long a1, volatile long a2, volatile long a3) { int fd = a0; uint8_t ep = a1; uint32_t len = a2; char* data = (char*)a3; int ep_handle = lookup_endpoint(fd, ep); if (ep_handle < 0) { return -1; } struct usb_raw_ep_io_data io_data; io_data.inner.ep = ep_handle; io_data.inner.flags = 0; if (len > sizeof(io_data.data)) len = sizeof(io_data.data); io_data.inner.length = len; int rv = usb_raw_ep_read(fd, (struct usb_raw_ep_io*)&io_data); if (rv < 0) { return rv; } memcpy(&data[0], &io_data.data[0], io_data.inner.length); sleep_ms(200); return 0; } 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)) { } } 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); } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { int iter = 0; DIR* dp = 0; const int umount_flags = MNT_FORCE | UMOUNT_NOFOLLOW; retry: while (umount2(dir, umount_flags) == 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, umount_flags) == 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, umount_flags)) 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, umount_flags)) 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 (;;) { 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; } remove_dir(cwdbuf); } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // bpf$PROG_LOAD arguments: [ // cmd: const = 0x5 (8 bytes) // arg: nil // size: len = 0x0 (8 bytes) // ] // returns fd_bpf_prog syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0ul, /*size=*/0ul); // openat$selinux_status arguments: [ // fd: const = 0xffffffffffffff9c (8 bytes) // file: nil // flags: const = 0x0 (4 bytes) // mode: const = 0x0 (2 bytes) // ] // returns fd syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0ul, /*flags=*/0, /*mode=*/0); // mkdir arguments: [ // path: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // mode: open_mode = 0x0 (8 bytes) // ] memcpy((void*)0x2000000000c0, "./bus\000", 6); syscall(__NR_mkdir, /*path=*/0x2000000000c0ul, /*mode=*/0ul); // mount$incfs arguments: [ // src: ptr[in, buffer] { // buffer: {2e 00} (length 0x2) // } // dst: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // type: ptr[in, buffer] { // buffer: {69 6e 63 72 65 6d 65 6e 74 61 6c 2d 66 73 00} (length 0xf) // } // flags: mount_flags = 0x1004002 (8 bytes) // opts: nil // ] memcpy((void*)0x2000000007c0, ".\000", 2); memcpy((void*)0x200000000800, "./bus\000", 6); memcpy((void*)0x200000000840, "incremental-fs\000", 15); syscall(__NR_mount, /*src=*/0x2000000007c0ul, /*dst=*/0x200000000800ul, /*type=*/0x200000000840ul, /*flags=MS_REC|MS_STRICTATIME|MS_NOSUID*/ 0x1004002ul, /*opts=*/0ul); // creat arguments: [ // file: nil // mode: open_mode = 0xb (8 bytes) // ] // returns fd syscall(__NR_creat, /*file=*/0ul, /*mode=S_IXOTH|S_IWOTH|S_IXGRP*/ 0xbul); // syz_usb_ep_read arguments: [ // fd: fd_usb (resource) // ep: int8 = 0x9 (1 bytes) // len: len = 0x0 (8 bytes) // data: nil // ] syz_usb_ep_read(/*fd=*/-1, /*ep=*/9, /*len=*/0, /*data=*/0); // socket$packet arguments: [ // domain: const = 0x11 (8 bytes) // type: packet_socket_type = 0x2 (8 bytes) // proto: const = 0x300 (4 bytes) // ] // returns sock_packet syscall(__NR_socket, /*domain=*/0x11ul, /*type=SOCK_DGRAM*/ 2ul, /*proto=*/0x300); // socket arguments: [ // domain: socket_domain = 0x2 (8 bytes) // type: socket_type = 0x3 (8 bytes) // proto: int32 = 0x6 (4 bytes) // ] // returns sock res = syscall(__NR_socket, /*domain=AF_INET*/ 2ul, /*type=SOCK_RAW*/ 3ul, /*proto=*/6); if (res != -1) r[0] = res; // bind$inet arguments: [ // fd: sock_in (resource) // addr: nil // addrlen: len = 0x0 (8 bytes) // ] syscall(__NR_bind, /*fd=*/r[0], /*addr=*/0ul, /*addrlen=*/0ul); // setsockopt$sock_int arguments: [ // fd: sock (resource) // level: const = 0x1 (4 bytes) // optname: sockopt_opt_sock_int = 0x6 (4 bytes) // optval: nil // optlen: len = 0x0 (8 bytes) // ] syscall(__NR_setsockopt, /*fd=*/r[0], /*level=*/1, /*optname=SO_BROADCAST*/ 6, /*optval=*/0ul, /*optlen=*/0ul); // sendto$inet arguments: [ // fd: sock_in (resource) // buf: nil // len: len = 0x0 (8 bytes) // f: send_flags = 0x48800 (8 bytes) // addr: nil // addrlen: len = 0x0 (8 bytes) // ] syscall(__NR_sendto, /*fd=*/r[0], /*buf=*/0ul, /*len=*/0ul, /*f=MSG_BATCH|MSG_MORE|MSG_CONFIRM*/ 0x48800ul, /*addr=*/0ul, /*addrlen=*/0ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000, /*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=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; use_temporary_dir(); do_sandbox_none(); return 0; }