In the Linux kernel, the following vulnerability has been resolved:
btrfs: tree-checker: validate names in ROOT_REF and ROOT_BACKREF
ROOT_REF and ROOT_BACKREF items contain a struct btrfs_root_ref followed
by the subvolume name. Several readers assume that this layout is already
valid and then use the on-disk name length directly. A corrupted item can
therefore make those readers address bytes outside the item, and
BTRFS_IOC_GET_SUBVOL_INFO can copy too many bytes into its fixed-size UAPI
name buffer.
Validate ROOT_REF and ROOT_BACKREF items in tree-checker before any reader
uses them. Reject records that do not contain a non-empty name, whose
name_len does not exactly describe the remaining item payload, or whose
name exceeds BTRFS_NAME_LEN. For BTRFS_IOC_GET_SUBVOL_INFO, copy only the validated on-disk name_len
instead of deriving the copy length from the item size.
The ioctl result is
zeroed when allocated. That leaves the existing trailing zero byte
untouched.
Attack Parameters
Impact Assessment
CVSS Vector v3.1