// https://syzkaller.appspot.com/bug?id=8f233777106f7963a180dc04bcf7b851743d1236 // 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 static unsigned long long procid; struct fs_image_segment { void* data; uintptr_t size; uintptr_t offset; }; #define IMAGE_MAX_SEGMENTS 4096 #define IMAGE_MAX_SIZE (129 << 20) #define sys_memfd_create 319 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(sys_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; } 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); 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\x00\x10\x00\x00\x00" "\x00\x00\x04\x00\x14\x00\xd0\x00\x02\x00\x04\x00\x00\x00\x1e\x00\x60\x00" "\x00\x00\x00\x00\xf5\x02\x00\x00\x00\x00\x00\x00\x99\x02\x00\x00\x00\x00" "\x00\x00\xdd\x02\x00\x00\x00\x00\x00\x00\x06\x01\x00\x00\x00\x00\x00\x00" "\xd4\x01\x00\x00\x00\x00\x00\x00\x4d\x02\x00\x00\x00\x00\x00\x00\x87\x02" "\x00\x00\x00\x00\x00\x00\xfd\x37\x7a\x58\x5a\x00\x00\x01\x69\x22\xde\x36" "\x02\xc0\x17\x64\x21\x01\x10\x00\x0c\x14\xf5\xca\xe0\x00\x63\x00\x0f\x5d" "\x00\x39\x9e\x4b\xac\xd2\x52\x69\x94\xd5\x12\xed\xa5\xbf\x00\x00\x00\x00" "\x4a\x55\x79\xb2\x00\x01\x27\x64\x0f\xa2\x9c\xb0\x90\x42\x99\x0d\x01\x00" "\x00\x00\x00\x01\x59\x5a\xfd\x37\x7a\x58\x5a\x00\x00\x01\x69\x22\xde\x36" "\x03\xc0\x1c\x9a\x08\x21\x01\x10\x00\x00\x00\x00\x93\xfc\x58\xde\xe0\x04" "\x19\x00\x14\x5d\x00\x39\x9e\x4b\xac\xd2\x52\x69\x94\xd5\x15\x08\xfe\x16" "\xca\x84\xa7\xaa\x36\x89\xdf\x00\x98\x88\x96\x66\x00\x01\x30\x9a\x08\x00" "\x00\x00\x2e\xc4\x2d\x99\x3e\x30\x0d\x8b\x02\x00\x00\x00\x00\x01\x59\x5a" "\x73\x79\x7a\x6b\x61\x6c\x6c\x65\x72\x73\xcc\x00\xfd\x37\x7a\x58\x5a\x00" "\x00\x01\x69\x22\xde\x36\x03\xc0\x94\x01\xbe\x02\x21\x01\x02\x00\x00\x00" "\x2b\xe6\xa3\x7d\xe0\x01\x3d\x00\x8c\x5d\x00\x01\x00\x1e\xb0\x4f\x26\x2e" "\x3c\x2f\x42\x2b\xdb\x8c\x11\x1c\x2e\xea\x0f\xf1\xb7\xf8\x7c\x3c\x98\x93" "\x0a\xe9\xbe\xf2\xe6\xcf\xbe\x86\x64\x2d\x31\x26\x30\xd1\xc1\x17\x7c\x3f" "\x02\xec\xcf\x24\xfa\x64\x58\x57\x4e\x29\x54\x84\x3d\xbd\x6b\xc9\x86\x80" "\x05\x03\x21\x63\x8c\x7a\x93\x37\x5d\xb1\xe7\x1b\xae\x62\x3d\x26\xe9\x09" "\x64\x27\xe1\x97\x37\x4c\x50\xe8\x29\xfa\x41\x6b\xd9\x3e\xb4\xfc\xf0\x67" "\xeb\x65\x0b\xe2\x18\x78\xe9\xae\x58\xde\x23\x3e\x58\x4b\xfa\x0f\x44\xd8" "\x59\x00\xda\xa9\x64\xd5\x3b\x67\xd7\xa1\x21\x5e\x51\x92\x89\x21\xae\xe7" "\x27\x93\x82\x66\x11\xb4\x3c\x00\xe5\x99\xfd\x79\x00\x01\xa8\x01\xbe\x02" "\x00\x00\x29\x83\x53\xf5\x3e\x30\x0d\x8b\x02\x00\x00\x00\x00\x01\x59\x5a" "\x77\x80\x01\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x24\x00\x00\x00" "\x02\x00\x04\x00\x66\x69\x6c\x65\x30\x48\x00\x01\x00\x03\x00\x04\x00\x66" "\x69\x6c\x65\x31\x04\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00" "\x00\x00\x02\x00\x08\x00\x66\x69\x6c\x65\x2e\x63\x6f\x6c\x64\x86\x00\x01" "\x00\x01\x00\x04\x00\x66\x69\x6c\x65\x30\xa6\x00\x04\x00\x02\x00\x04\x00" "\x66\x69\x6c\x65\x31\xe2\x00\x05\x00\x02\x00\x04\x00\x66\x69\x6c\x65\x32" "\xe2\x00\x05\x00\x02\x00\x04\x00\x66\x69\x6c\x65\x33\x38\x80\x00\x00\x00" "\x00\x00\x00\x00\x00\x86\x00\x00\x00\x00\x00\x00\x00\x24\x00\x00\x00\x00" "\x00\x00\x00\x48\x00\x00\x00\x00\x00\x00\x00\xa6\x00\x00\x00\x00\x00\x00" "\x00\xe2\x00\x00\x00\x00\x00\x00\x00\x1e\x01\x00\x00\x00\x00\x00\x00\x4d" "\x02\x00\x00\x00\x00\x00\x00\x08\x80\x5c\xf9\x01\x00\x53\x5f\x01\x00\x8f" "\x02\x00\x00\x00\x00\x00\x00\x28\x80\x00\x00\x06\x00\x78\x61\x74\x74\x72" "\x31\x06\x00\x00\x00\x78\x61\x74\x74\x72\x31\x00\x00\x06\x00\x78\x61\x74" "\x74\x72\x32\x06\x00\x00\x00\x78\x61\x74\x74\x72\x32\x10\x80\x00\x00\x00" "\x00\x00\x00\x00\x00\x02\x00\x00\x00\x24\x00\x00\x00\xa1\x02\x00\x00\x00" "\x00\x00\x00\x01", 742); *(uint64_t*)0x20000208 = 0x2e6; *(uint64_t*)0x20000210 = 0; *(uint8_t*)0x20010300 = 0; syz_mount_image(0x20000000, 0x20000100, 0x1000, 1, 0x20000200, 0, 0x20010300); return 0; }