CVE-2026-64432

Description

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: validate Dirty Page Table capacity in log_replay copy_lcns In the analysis pass of $LogFile journal replay, log_replay() copies LCNs from each action log record into an existing Dirty Page Table (DPT) entry without bounding the destination index. A crafted NTFS image with DPT entry lcns_follow=1 and an action log record with lcns_follow=2 produces a kernel slab out-of-bounds write at mount time: BUG: KASAN: slab-out-of-bounds in log_replay+0x654c/0xdb60 Write of size 8 at addr ffff8880095e1040 by task mount Two attacker-controlled fields can drive j+i past the allocated page_lcns[] array: 1. dp->lcns_follow (capacity) can be smaller than lrh->lcns_follow. 2. lrh->target_vcn may be smaller than dp->vcn, making the u64 subtraction wrap to a huge size_t. Validate target VCN delta and per-record LCN count against the DPT entry capacity, bail via the existing out: cleanup label with -EINVAL. This mirrors the bounds-check pattern added in commit b2bc7c44ed17 ("fs/ntfs3: Fix slab-out-of-bounds read in DeleteIndexEntryRoot") and commit 0ca0485e4b2e ("fs/ntfs3: validate rec->used in journal-replay file record check").

References

• https://git.kernel.org/stable/c/3aa96956ca2200674e2a8f9c23ec6ecd45e5010f
• https://git.kernel.org/stable/c/57382ec6ac63b63dce2789e835fded28b698ae79
• https://git.kernel.org/stable/c/946046841013ebac8492ef49651c53638d7a9a6a
• https://git.kernel.org/stable/c/964c3fae1dfc49dde5468eace940f199cda234e9
• https://git.kernel.org/stable/c/c6f9e804f73ef809529865fbc7256dd189ff8c33