Affected: Alpaquita:23: linux-lts, Alpaquita:25: linux-lts, Alpaquita:stream: linux-lts

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]

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]

kernel-devel-7.2.7-1.1 on GA media

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 193 more

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]

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um Sicherheitsmaßnahmen zu umgehen, Daten oder den Systemzustand zu manipulieren, Denial-of-Service-Zustände herbeizuführen oder andere, nicht näher spezifizierte Angriffe durchzuführen.