// https://syzkaller.appspot.com/bug?id=050dde6a74647ce7473ff025858df08277c7068f // 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 #ifndef __NR_memfd_create #define __NR_memfd_create 279 #endif #ifndef __NR_mmap #define __NR_mmap 222 #endif #ifndef __NR_mount #define __NR_mount 40 #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; } struct fs_image_segment { void* data; uintptr_t size; uintptr_t offset; }; #define IMAGE_MAX_SEGMENTS 4096 #define IMAGE_MAX_SIZE (129 << 20) static unsigned long fs_image_segment_check(unsigned long size, unsigned long nsegs, struct fs_image_segment* segs) { if (nsegs > IMAGE_MAX_SEGMENTS) nsegs = IMAGE_MAX_SEGMENTS; for (size_t i = 0; i < nsegs; i++) { if (segs[i].size > IMAGE_MAX_SIZE) segs[i].size = IMAGE_MAX_SIZE; segs[i].offset %= IMAGE_MAX_SIZE; if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size) segs[i].offset = IMAGE_MAX_SIZE - segs[i].size; if (size < segs[i].offset + segs[i].offset) size = segs[i].offset + segs[i].offset; } if (size > IMAGE_MAX_SIZE) size = IMAGE_MAX_SIZE; return size; } static int setup_loop_device(long unsigned size, long unsigned nsegs, struct fs_image_segment* segs, const char* loopname, int* memfd_p, int* loopfd_p) { int err = 0, loopfd = -1; size = fs_image_segment_check(size, nsegs, segs); int memfd = syscall(__NR_memfd_create, "syzkaller", 0); if (memfd == -1) { err = errno; goto error; } if (ftruncate(memfd, size)) { err = errno; goto error_close_memfd; } for (size_t i = 0; i < nsegs; i++) { if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) { } } loopfd = open(loopname, O_RDWR); if (loopfd == -1) { err = errno; goto error_close_memfd; } if (ioctl(loopfd, LOOP_SET_FD, memfd)) { if (errno != EBUSY) { err = errno; goto error_close_loop; } ioctl(loopfd, LOOP_CLR_FD, 0); usleep(1000); if (ioctl(loopfd, LOOP_SET_FD, memfd)) { err = errno; goto error_close_loop; } } *memfd_p = memfd; *loopfd_p = loopfd; return 0; error_close_loop: close(loopfd); error_close_memfd: close(memfd); error: errno = err; return -1; } static long syz_mount_image(volatile long fsarg, volatile long dir, volatile unsigned long size, volatile unsigned long nsegs, volatile long segments, volatile long flags, volatile long optsarg) { struct fs_image_segment* segs = (struct fs_image_segment*)segments; int res = -1, err = 0, loopfd = -1, memfd = -1, need_loop_device = !!segs; char* mount_opts = (char*)optsarg; char* target = (char*)dir; char* fs = (char*)fsarg; char* source = NULL; char loopname[64]; if (need_loop_device) { memset(loopname, 0, sizeof(loopname)); snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid); if (setup_loop_device(size, nsegs, segs, loopname, &memfd, &loopfd) == -1) return -1; source = loopname; } mkdir(target, 0777); char opts[256]; memset(opts, 0, sizeof(opts)); if (strlen(mount_opts) > (sizeof(opts) - 32)) { } strncpy(opts, mount_opts, sizeof(opts) - 32); if (strcmp(fs, "iso9660") == 0) { flags |= MS_RDONLY; } else if (strncmp(fs, "ext", 3) == 0) { if (strstr(opts, "errors=panic") || strstr(opts, "errors=remount-ro") == 0) strcat(opts, ",errors=continue"); } else if (strcmp(fs, "xfs") == 0) { strcat(opts, ",nouuid"); } res = mount(source, target, fs, flags, opts); if (res == -1) { err = errno; goto error_clear_loop; } res = open(target, O_RDONLY | O_DIRECTORY); if (res == -1) { err = errno; } error_clear_loop: if (need_loop_device) { ioctl(loopfd, LOOP_CLR_FD, 0); close(loopfd); close(memfd); } errno = err; return res; } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { int iter = 0; DIR* dp = 0; retry: while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 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, MNT_DETACH | UMOUNT_NOFOLLOW) == 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, MNT_DETACH | UMOUNT_NOFOLLOW)) 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, MNT_DETACH | UMOUNT_NOFOLLOW)) 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 reset_loop() { char buf[64]; snprintf(buf, sizeof(buf), "/dev/loop%llu", procid); int loopfd = open(buf, O_RDWR); if (loopfd != -1) { ioctl(loopfd, LOOP_CLR_FD, 0); close(loopfd); } } 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); reset_loop(); 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); } } void execute_one(void) { *(uint64_t*)0x20000200 = 0; *(uint64_t*)0x20000208 = 0; *(uint64_t*)0x20000210 = 0x400; *(uint64_t*)0x20000218 = 0; *(uint64_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0x800; *(uint64_t*)0x20000230 = 0; *(uint64_t*)0x20000238 = 0; *(uint64_t*)0x20000240 = 0x1400; syz_mount_image(0, 0, 0, 3, 0x20000200, 0, 0); memcpy((void*)0x20000000, "reiserfs\000", 9); memcpy((void*)0x20000100, "./file0\000", 8); *(uint64_t*)0x20000200 = 0x20010000; memcpy((void*)0x20010000, "\x00\x40\x00\x00\x68\x02\x00\x00\x97\x3d\x00\x00\x12\x00\x00\x00\x00" "\x00\x00\x00\x84\x3d\x00\x00\x00\x01\x00\x00\x73\x56\x4d\x38\xe1\x00" "\x00\x00\x1e\x00\x00\x00\x00\x00\x00\x00\x00\x10\xcc\x03\x02\x00\x01" "\x00\x52\x65\x49\x73\x45\x72\x33\x46\x73\x00\x00\x00\x01\x00\x00\x00" "\x02\x00\x01\x00\x02\x00\x85\x3d\x00\x00\x00\x00\x01\x00\x00\x00\x12" "\x31\x23\x12\x12\x33\x12\x33\x12\x31\x12\x34\x13\x41\x24\x12\x73\x79" "\x7a\x6b\x61\x6c\x6c\x65\x72\x00\x00\x00\x00\x00\x00\x00\x01\x00\x1e" "\x00\x3b\xc1\x65\x5f\x00\x4e\xed\x00", 128); *(uint64_t*)0x20000208 = 0x80; *(uint64_t*)0x20000210 = 0x10000; *(uint64_t*)0x20000218 = 0; *(uint64_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0x100c0; *(uint64_t*)0x20000230 = 0; *(uint64_t*)0x20000238 = 0; *(uint64_t*)0x20000240 = 0x11000; *(uint64_t*)0x20000248 = 0; *(uint64_t*)0x20000250 = 0; *(uint64_t*)0x20000258 = 0x11800; *(uint64_t*)0x20000260 = 0x20011200; memcpy((void*)0x20011200, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x12\x00\x00\x00\x00" "\x00\x00\x00\x84\x3d\x00\x00\x00\x01\x00\x00\x73\x56\x4d\x38\xe1\x00" "\x00\x00\x1e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 64); *(uint64_t*)0x20000268 = 0x40; *(uint64_t*)0x20000270 = 0x3d96000; *(uint64_t*)0x20000278 = 0x20011300; memcpy((void*)0x20011300, "\x01\x00\x02\x00\x5c\x0f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x2c\x00\xd4\x0f\x01\x00\x01\x00\x00" "\x00\x02\x00\x00\x00\x01\x00\x00\x00\xf4\x01\x00\x00\x02\x00\x30\x00" "\xa4\x0f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 96); *(uint64_t*)0x20000280 = 0x60; *(uint64_t*)0x20000288 = 0x3d97000; *(uint64_t*)0x20000290 = 0x20011400; memcpy((void*)0x20011400, "\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x28" "\x00\x04\x00\x02\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x20\x00" "\x04\x00\x2e\x2e\x00\x00\x00\x00\x00\x00\x2e\x00\x00\x00\x00\x00\x00" "\x00\xed\x41\x00\x00\x03\x00\x00\x00\x30\x00\x00\x00\x00\x00\x00\x00" "\x5c\xf9\x01\x00\x53\x5f\x01\x00\x3b\xc1\x65\x5f\x3b\xc1\x65\x5f\x3b" "\xc1\x65\x5f\x01\x00\x00\x00\x00\x00\x00\x00", 96); *(uint64_t*)0x20000298 = 0x60; *(uint64_t*)0x200002a0 = 0x3d97fa0; *(uint8_t*)0x20011500 = 0; syz_mount_image(0x20000000, 0x20000100, 0x4000000, 7, 0x20000200, 0, 0x20011500); memcpy((void*)0x20000000, "squashfs\000", 9); memcpy((void*)0x20000100, "./file0\000", 8); *(uint64_t*)0x20000200 = 0x20010000; memcpy( (void*)0x20010000, "\x68\x73\x71\x73\x07\x00\x00\x00\x91\x1d\x67\x5f\x00\x10\x00\x00\x00\x00" "\x00\x00\x01\x00\x0c\x00\xd0\x00\x02\x00\x04\x00\x00\x00\x26\x01\x00\x00" "\x00\x00\x04\x00\x06\x02\x00\x00\x00\x00\x00\x00\xb5\x01\x00\x00\x00\x00" "\x00\x00\xee\x01\x00\x00\x00\x00\x00\x00\x99\x00\x00\x00\x00\x00\x00\x00" "\x3e\x01\x00\x00\x00\x00\x00\x00\x85\x01\x00\x00\x00\x00\x00\x00\xa3\x01" "\x00\x00\x00\x00\x00\x00\x78\xda\x2b\xae\xac\xca\x4e\xcc\xc9\x49\x2d\x2a" "\xa6\x1d\x03\x00\x85\x49\x2b\x1f\x78\xda\x2b\xae\xac\xca\x4e\xcc\xc9\x49" "\x2d\x2a\x1e\x65\x8c\x32\x46\x19\xa3\x0c\x18\x03\x00\x55\x65\xc4\xa2\x73" "\x79\x7a\x6b\x61\x6c\x6c\x65\x72\x73\xa3\x00\x78\xda\x63\x62\x78\xcb\xc8" "\xc0\xc0\xc8\x30\x51\x36\x3d\x1e\xc8\x60\x48\x00\xe2\xff\x40\x00\xa4\x18" "\x52\x80\x58\x04\x88\x99\x90\xd4\x30\x03\xf9\x25\x48\x6a\xa4\x58\x18\x18" "\xa4\x81\x34\x33\xc3\x7f\xb8\x1a\xa0\x10\x03\xc8\x2c\x35\x20\xd6\x2f\xc9" "\x2d\xd0\x2f\xae\xac\xd2\xcd\xcc\x4d\x4c\x4f\x4d\x4f\xcd\x33\x31\xb4\x34" "\x37\x37\x33\xb6\x34\xd2\x4f\xcb\xcc\x49\x35\x80\x90\x8c\x48\x36\x30\x31" "\x40\x00\x88\xd6\x04\x62\x76\x20\xe6\x44\x92\x67\x05\xf2\xfb\xa1\x6a\xb8" "\x18\x50\x01\x23\x92\xcb\xa0\xf2\x8c\xc8\x7a\xd9\x80\x62\x33\xa1\x72\x1a" "\xca\xa8\x7a\x99\x90\xf4\x22\x9b\x01\x31\xf7\x00\xdc\x0c\x76\xa8\x18\x28" "\x24\x42\x80\x7e\xe4\x00\xd2\x00\x8b\x6a\x35\x09\x45\x00\x78\xda\x63\x64" "\x80\x00\x66\x20\x56\x01\x62\x26\x06\x16\x86\xb4\xcc\x9c\x54\x03\x0f\x06" "\x46\xa0\x20\x84\x63\xc8\x02\x55\xc5\x08\xa5\x99\x18\x38\xc0\x12\x7a\xc9" "\xf9\x39\x29\x6d\x40\x61\x46\x98\xb6\x65\x40\x06\xcc\x0c\xc3\x47\x0c\xac" "\x70\x8e\x11\x32\xc7\x18\x00\x42\x1f\x11\xfb\x1c\x00\x78\xda\x63\x60\x80" "\x80\x36\x28\xad\x02\xa5\x3d\xa0\xf4\x32\x28\xfd\x08\x4a\xab\x31\x42\x68" "\x00\x46\xdf\x02\xa2\x85\x01\x00\x00\x00\x00\x00\x00\x08\x80\x5c\xf9\x01" "\x00\x53\x5f\x01\x00\xab\x01\x00\x00\x00\x00\x00\x00\x1d\x00\x78\xda\x63" "\x60\x60\x63\xa8\x48\x2c\x29\x29\x32\x64\x63\x60\x80\xb2\x18\x60\x62\x46" "\x70\x31\x23\x00\xb5\xbc\x09\xab\x10\x80\x00\x00\x00\x00\x00\x00\x00\x00" "\x02\x00\x00\x00\x24\x00\x00\x00\xbd\x01\x00\x00\x00\x00\x00\x00\x01\x00" "\x00\x00\x00\x00\x00\x00\xdc\x01", 512); *(uint64_t*)0x20000208 = 0x200; *(uint64_t*)0x20000210 = 0; syz_mount_image(0x20000000, 0x20000100, 0x100b, 1, 0x20000200, 0, 0x20000140); memcpy((void*)0x20002540, "./file0/file0\000", 14); syscall(__NR_mount, 0ul, 0x20002540ul, 0ul, 0ul, 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); use_temporary_dir(); loop(); return 0; }