CVE-2025-21815 Information

Description

In the Linux kernel the following vulnerability has been resolved:

mm/compaction: fix UBSAN shift-out-of-bounds warning

syzkaller reported a UBSAN shift-out-of-bounds warning of (1UL « order) in isolate_freepages_block(). The bogus compound_order can be any value because it is union with flags. Add back the MAX_PAGE_ORDER check to fix the warning.

Reference

https://git.kernel.org/stable/c/10b7d3eb535098ccd4c82a182a33655d8a0e5c88 https://git.kernel.org/stable/c/4491159774d973a9e2e998d25d8fbb20fada6dfa https://git.kernel.org/stable/c/d1366e74342e75555af2648a2964deb2d5c92200