IT

Tracker / CVE-2026-23234

CVE-2026-23234

High 7.8

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid UAF in f2fs_write_end_io() As syzbot reported an use-after-free issue in f2fs_write_end_io(). It is caused by below race condition: loop device umount - worker_thread - loop_process_work - do_req_filebacked - lo_rw_aio - lo_rw_aio_complete - blk_mq_end_request - blk_update_request - f2fs_write_end_io - dec_page_count - folio_end_writeback - kill_f2fs_super - kill_block_super - f2fs_put_super : free(sbi) : get_pages(, F2FS_WB_CP_DATA) accessed sbi which is freed In kill_f2fs_super(), we will drop all page caches of f2fs inodes before call free(sbi), it guarantee that all folios should end its writeback, so it should be safe to access sbi before last folio_end_writeback(). Let's relocate ckpt thread wakeup flow before folio_end_writeback() to resolve this issue.

Affected products and versions

linux linux_kernel · 3.13 → 5.10.251
linux linux_kernel · 5.11 → 5.15.201
linux linux_kernel · 5.16 → 6.1.164
linux linux_kernel · 6.13 → 6.18.13
linux linux_kernel · 6.19 → 6.19.3
linux linux_kernel · 6.2 → 6.6.127
linux linux_kernel · 6.7 → 6.12.74

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References