// https://syzkaller.appspot.com/bug?id=bf3cb7481f41e76229e4231d4e4a8d364a04a0df // 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 #ifndef __NR_bpf #define __NR_bpf 321 #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 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 FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { int iter = 0; DIR* dp = 0; retry: const int umount_flags = MNT_FORCE | UMOUNT_NOFOLLOW; 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 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(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } remove_dir(cwdbuf); } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } *(uint32_t*)0x20000580 = 0xa; *(uint32_t*)0x20000584 = 4; *(uint32_t*)0x20000588 = 4; *(uint32_t*)0x2000058c = 4; *(uint32_t*)0x20000590 = 0; *(uint32_t*)0x20000594 = 1; *(uint32_t*)0x20000598 = 0; memset((void*)0x2000059c, 0, 16); *(uint32_t*)0x200005ac = 0; *(uint32_t*)0x200005b0 = -1; *(uint32_t*)0x200005b4 = 0; *(uint32_t*)0x200005b8 = 0; *(uint32_t*)0x200005bc = 0; *(uint64_t*)0x200005c0 = 0; res = syscall(__NR_bpf, /*cmd=*/0ul, /*arg=*/0x20000580ul, /*size=*/0x48ul); if (res != -1) r[0] = res; *(uint32_t*)0x200000c0 = 0x11; *(uint32_t*)0x200000c4 = 0x14; *(uint64_t*)0x200000c8 = 0x200002c0; memcpy((void*)0x200002c0, "\x18\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x18" "\x11\x00\x00", 20); *(uint32_t*)0x200002d4 = r[0]; memcpy((void*)0x200002d8, "\x00\x00\x00\x00\x00\x00\x00\x00\xb7\x08\x00\x00\xfc\xff\xff\xff\x7b" "\x8a\xf8\xff\x00\x00\x00\x00\xbf\xa2\x00\x00\x00\x00\x00\x00\x07\x02" "\x00\x00\xf8\xff\xff\xff\xb7\x03\x00\x00\x08\x23\x00\x00\xb7\x04\x00" "\x00\x00\x00\x00\x00\x85\x00\x00\x00\x01\x00\x00\x00\x18\x01\x00\x00" "\x20\x20\x73\x25\x00\x00\x00\x00\x00\x20\x20\x20\x7b\x1a\xf8\xff\x00" "\x00\x00\x00\xbf\xa1\x00\x00\x00\x00\x00\x00\x07\x01\x00\x00\xf8\xff" "\xff\xff\xb7\x02\x00\x00\x08\x00\x00\x00\xb7\x03\x00\x00\x00\x00\x60" "\xff\x85\x00\x00\x00\x04\x00\x00\x00\x95", 129); *(uint64_t*)0x200000d0 = 0x20000240; memcpy((void*)0x20000240, "GPL\000", 4); *(uint32_t*)0x200000d8 = 0; *(uint32_t*)0x200000dc = 0; *(uint64_t*)0x200000e0 = 0; *(uint32_t*)0x200000e8 = 0; *(uint32_t*)0x200000ec = 0; memset((void*)0x200000f0, 0, 16); *(uint32_t*)0x20000100 = 0; *(uint32_t*)0x20000104 = 0; *(uint32_t*)0x20000108 = -1; *(uint32_t*)0x2000010c = 0; *(uint64_t*)0x20000110 = 0; *(uint32_t*)0x20000118 = 0; *(uint32_t*)0x2000011c = 0; *(uint64_t*)0x20000120 = 0; *(uint32_t*)0x20000128 = 0; *(uint32_t*)0x2000012c = 0; *(uint32_t*)0x20000130 = 0; *(uint32_t*)0x20000134 = 0; *(uint64_t*)0x20000138 = 0; *(uint64_t*)0x20000140 = 0; *(uint32_t*)0x20000148 = 0; *(uint32_t*)0x2000014c = 0; res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200000c0ul, /*size=*/0x90ul); if (res != -1) r[1] = res; *(uint64_t*)0x20000180 = 0x20000140; memcpy((void*)0x20000140, "ext4_ext_remove_space_done\000", 27); *(uint32_t*)0x20000188 = r[1]; syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x20000180ul, /*size=*/0x10ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); const char* reason; (void)reason; for (procid = 0; procid < 5; procid++) { if (fork() == 0) { use_temporary_dir(); loop(); } } sleep(1000000); return 0; }