In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: prevent uninitialized lcn caused by zero len syzbot reported a uninit-value in ntfs_iomap_begin [1]. Since runs was not touched yet, run_lookup_entry() immediately fails and returns false, which makes the value of "*len" 0. Simultaneously, the new value and err value are also 0, causing the logic in attr_data_get_block_locked() to jump directly to ok, ultimately resulting in *lcn being triggered before it is set [1]