// https://syzkaller.appspot.com/bug?id=4ccf74c59eeaeb45b6f5a0dc24b94d4ce4ced9d0 // 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 #ifndef __NR_fsconfig #define __NR_fsconfig 431 #endif #ifndef __NR_fsmount #define __NR_fsmount 432 #endif #ifndef __NR_fsopen #define __NR_fsopen 430 #endif static unsigned long long procid; 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 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 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 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(); 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[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // prctl$PR_SCHED_CORE arguments: [ // option: const = 0x3e (8 bytes) // cmd: intptr = 0x1 (8 bytes) // pid: pid (resource) // type: pid_type = 0x1 (8 bytes) // uaddr: nil // ] syscall(__NR_prctl, /*option=*/0x3eul, /*cmd=*/1ul, /*pid=*/0, /*type=PIDTYPE_TGID*/ 1ul, /*uaddr=*/0ul); // prlimit64 arguments: [ // pid: pid (resource) // res: rlimit_type = 0xe (8 bytes) // new: ptr[in, rlimit] { // rlimit { // soft: intptr = 0x8 (8 bytes) // hard: intptr = 0x100008b (8 bytes) // } // } // old: nil // ] *(uint64_t*)0x200000000380 = 8; *(uint64_t*)0x200000000388 = 0x100008b; syscall(__NR_prlimit64, /*pid=*/0, /*res=RLIMIT_RTPRIO*/ 0xeul, /*new=*/0x200000000380ul, /*old=*/0ul); // sched_setscheduler arguments: [ // pid: pid (resource) // policy: sched_policy = 0x1 (8 bytes) // prio: ptr[in, int32] { // int32 = 0x5 (4 bytes) // } // ] *(uint32_t*)0x200000000200 = 5; syscall(__NR_sched_setscheduler, /*pid=*/0, /*policy=SCHED_FIFO*/ 1ul, /*prio=*/0x200000000200ul); // writev arguments: [ // fd: fd (resource) // vec: nil // vlen: len = 0x0 (8 bytes) // ] syscall(__NR_writev, /*fd=*/(intptr_t)-1, /*vec=*/0ul, /*vlen=*/0ul); // fsopen arguments: [ // type: ptr[in, buffer] { // buffer: {72 61 6d 66 73 00} (length 0x6) // } // flags: fsopen_flags = 0x0 (8 bytes) // ] // returns fd_fscontext memcpy((void*)0x2000000001c0, "ramfs\000", 6); res = syscall(__NR_fsopen, /*type=*/0x2000000001c0ul, /*flags=*/0ul); if (res != -1) r[0] = res; // fsconfig$FSCONFIG_CMD_CREATE arguments: [ // fd: fd_fscontext (resource) // cmd: const = 0x6 (8 bytes) // key: const = 0x0 (8 bytes) // value: const = 0x0 (8 bytes) // aux: const = 0x0 (8 bytes) // ] syscall(__NR_fsconfig, /*fd=*/r[0], /*cmd=*/6ul, /*key=*/0ul, /*value=*/0ul, /*aux=*/0ul); // fsmount arguments: [ // fs_fd: fd_fscontext (resource) // flags: fsmount_flags = 0x0 (8 bytes) // attr_flags: fsmount_attr_flags = 0x0 (8 bytes) // ] // returns fd res = syscall(__NR_fsmount, /*fs_fd=*/r[0], /*flags=*/0ul, /*attr_flags=*/0ul); if (res != -1) r[1] = res; // fchown arguments: [ // fd: fd (resource) // uid: uid (resource) // gid: gid (resource) // ] syscall(__NR_fchown, /*fd=*/(intptr_t)-1, /*uid=*/0, /*gid=*/0); // fchdir arguments: [ // fd: fd (resource) // ] syscall(__NR_fchdir, /*fd=*/r[1]); // open arguments: [ // file: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: open_flags = 0x143142 (8 bytes) // mode: open_mode = 0x80 (8 bytes) // ] // returns fd memcpy((void*)0x200000000040, "./bus\000", 6); syscall(__NR_open, /*file=*/0x200000000040ul, /*flags=O_SYNC|O_NOCTTY|O_NOATIME|O_CREAT|FASYNC|0x2*/ 0x143142ul, /*mode=S_IWUSR*/ 0x80ul); // openat arguments: [ // fd: fd_dir (resource) // file: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: open_flags = 0x0 (4 bytes) // mode: open_mode = 0x10 (2 bytes) // ] // returns fd memcpy((void*)0x200000000080, "./bus\000", 6); res = syscall(__NR_openat, /*fd=*/r[1], /*file=*/0x200000000080ul, /*flags=*/0, /*mode=S_IWGRP*/ 0x10); if (res != -1) r[2] = res; // openat arguments: [ // fd: fd_dir (resource) // file: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: open_flags = 0x1c1002 (4 bytes) // mode: open_mode = 0x50 (2 bytes) // ] // returns fd memcpy((void*)0x200000000000, "./bus\000", 6); res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x200000000000ul, /*flags=O_SYNC|O_NOATIME|O_CLOEXEC|O_RDWR*/ 0x1c1002, /*mode=S_IWGRP|S_IXUSR*/ 0x50); if (res != -1) r[3] = res; // write arguments: [ // fd: fd (resource) // buf: ptr[in, buffer] { // buffer: {74} (length 0x1) // } // count: len = 0x1 (8 bytes) // ] memset((void*)0x200000004200, 116, 1); syscall(__NR_write, /*fd=*/r[3], /*buf=*/0x200000004200ul, /*count=*/1ul); // sendfile arguments: [ // fdout: fd (resource) // fdin: fd (resource) // off: nil // count: intptr = 0x7fffffff (8 bytes) // ] syscall(__NR_sendfile, /*fdout=*/r[3], /*fdin=*/r[2], /*off=*/0ul, /*count=*/0x7ffffffful); // mkdir arguments: [ // path: nil // mode: open_mode = 0x0 (8 bytes) // ] syscall(__NR_mkdir, /*path=*/0ul, /*mode=*/0ul); // mkdir arguments: [ // path: nil // mode: open_mode = 0xa5 (8 bytes) // ] syscall(__NR_mkdir, /*path=*/0ul, /*mode=S_IXOTH|S_IROTH|S_IRGRP|S_IWUSR*/ 0xa5ul); // mkdir arguments: [ // path: nil // mode: open_mode = 0x0 (8 bytes) // ] syscall(__NR_mkdir, /*path=*/0ul, /*mode=*/0ul); // mknodat$loop arguments: [ // dirfd: fd_dir (resource) // file: nil // mode: mknod_mode = 0x0 (8 bytes) // dev: proc = 0x0 (4 bytes) // ] syscall(__NR_mknodat, /*dirfd=*/(intptr_t)-1, /*file=*/0ul, /*mode=*/0ul, /*dev=*/0x700 + procid * 2); // linkat arguments: [ // oldfd: fd_dir (resource) // old: nil // newfd: fd_dir (resource) // new: nil // flags: linkat_flags = 0x0 (8 bytes) // ] syscall(__NR_linkat, /*oldfd=*/(intptr_t)-1, /*old=*/0ul, /*newfd=*/(intptr_t)-1, /*new=*/0ul, /*flags=*/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; for (procid = 0; procid < 5; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }