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").

Fixes: b46acd6a6a62 ("fs/ntfs3: Add NTFS journal")
Reported-by: Yunpeng Tian <shionthanatos@gmail.com>
Reported-by: Mingda Zhang <npczmd@qq.com>
Reported-by: Gongming Wang <gmwgg05@gmail.com>
Reported-by: Peiyuan Xu <paulbucket12@gmail.com>
Reported-by: Qinrun Dai <jupmouse@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Yunpeng Tian <shionthanatos@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

0 files changed, 0 insertions, 0 deletions