CVE-2026-53029

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fs/ntfs3: prevent uninitialized lcn caused by zero len<br /> <br /> syzbot reported a uninit-value in ntfs_iomap_begin [1].<br /> <br /> Since runs was not touched yet, run_lookup_entry() immediately fails<br /> and returns false, which makes the value of "*len" 0.<br /> Simultaneously, the new value and err value are also 0, causing the<br /> logic in attr_data_get_block_locked() to jump directly to ok, ultimately<br /> resulting in *lcn being triggered before it is set [1].<br /> <br /> In ntfs_iomap_begin(), the check for a 0 value in clen is moved forward<br /> to before updating lcn to avoid this [1].<br /> <br /> [1]<br /> BUG: KMSAN: uninit-value in ntfs_iomap_begin+0x8c0/0x1460 fs/ntfs3/inode.c:825<br /> ntfs_iomap_begin+0x8c0/0x1460 fs/ntfs3/inode.c:825<br /> iomap_iter+0x9b7/0x1540 fs/iomap/iter.c:110<br /> <br /> Local variable lcn created at:<br /> ntfs_iomap_begin+0x15d/0x1460 fs/ntfs3/inode.c:786