CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's f2fs filesystem, specifically in the redirty_blocks() function, which improperly handles pinned folios during a cleanup loop. This flaw can lead to a "BUG: Bad page state" error due to excessive reference drops on folios that were not successfully pinned, potentially destabilizing the system. Linux kernel maintainers and users of affected distributions should prioritize this issue to ensure system stability and prevent potential crashes.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: only redirty pinned folios in redirty_blocks redirty_blocks() pins folios with read_cache_folio() and then walks the same range again with filemap_lock_folio() to redirty them and drop the references it took. Commit 5951fee46bef ("f2fs: Use a folio in redirty_blocks()") changed the second pass to a do/while loop. If read_cache_folio() fails before anything is pinned, page_idx does not advance but the cleanup loop still runs once. If readahead has already populated the failed folio in page cache, that extra iteration finds it and folio_put_refs(folio, 2) drops one reference too many. Later drop_caches or reclaim can then report "BUG: Bad page state". Only redirty the range that was pinned successfully.