fs/ntfs3: bound page_lcns[] index by the log record

The copy_lcns loop and the redo shorten loop index page_lcns[] at j + i,
where i runs up to the log record's lcns_follow. That count is checked only
against the record's own length, not the target entry, so check_dp_table()
(which validates the entry's lcns_follow) does not cover it: the copy_lcns
entry may even be freshly allocated after that check, and find_dp() bounds j
but not i. A crafted record thus overflows page_lcns[] of an otherwise valid
entry.

Add dp_range_ok() and reject, before each loop, any record whose run does
not fit the entry. These are the only two page_lcns[] accesses indexed by
the record rather than the entry, so together with the entry validation
every access is now bounded.

Fixes: b46acd6a6a62 ("fs/ntfs3: Add NTFS journal")
Cc: stable@vger.kernel.org
Reported-by: Weiming Shi <bestswngs@gmail.com>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Xiang Mei <xmei5@asu.edu>
[almaz.alexandrovich@paragon-software.com: original patch contained changes to the problem already handled, applied partly]
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

0 files changed, 0 insertions, 0 deletions