CVE-2026-72159
CVE-2026-72159CVE-2026-72159
Description
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: reject non-inline dinodes with i_size and zero i_clusters
On a volume mounted without OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC, a
non-inline regular file with non-zero i_size and zero i_clusters is
structurally malformed: the extent map declares no allocated clusters yet
the size header claims content exists. Keep rejecting that shape, but
express it through a shared predicate so the same invariant is available
to normal inode reads and online filecheck.
The same zero-cluster shape is also malformed for non-inline directories.
ocfs2 directory growth allocates backing storage before advancing i_size,
and ocfs2_dir_foreach_blk_el() later walks until ctx->pos reaches
i_size_read(inode). A forged directory dinode with a huge i_size and no
clusters would repeatedly fail on holes while advancing through the
claimed size.
Sparse regular files remain exempt: on sparse-alloc volumes, truncate can
legitimately grow i_si
Scoring
| Last modified | 2026-08-15 |