CVE-2026-89615fs/ntfs3: bound page_lcns[] index by the log record

Official description

In the Linux kernel, the following vulnerability has been resolved: 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. [almaz.alexandrovich@paragon-software.com: original patch contained changes to the problem already handled, applied partly]

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/31fdd11f75da9823500168cecb07aa45130915a3
• https://git.kernel.org/stable/c/bb742d1030864c0fe140666f639428ba4e90b2ca
• https://git.kernel.org/stable/c/61ca8cbbf68f77f25b699ed4358bd232f94ed43b
• https://git.kernel.org/stable/c/f4c1bc6d7331f344ffcea93c2a37badcbe15baa6
• https://git.kernel.org/stable/c/7ccb94901f38a062034b56b43c774050b113758f
• https://git.kernel.org/stable/c/1135ebc225996b3ac1a295652b19a0a706737a6c
• https://git.kernel.org/stable/c/6f7b9dbdc1b7520206abce0049bdd143eb536e75