CVE-2026-68459

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix potential deadlock in gc_merge path of f2fs_balance_fs()

When we mount device w/ gc_merge mount option, we may suffer below

potential deadlock:

Kworker GC trehad Truncator

- f2fs_write_cache_pages

- f2fs_write_single_data_page

- f2fs_do_write_data_page

- folio_start_writeback --- set writeback flag on folio

- f2fs_outplace_write_data

: cached folio in internal bio cache

- f2fs_balance_fs

- wake_up(gc_thread)

: wake up gc thread to run foreground GC

- finish_wait(fggc_wq)

: wait on the waitqueue --- wait on GC thread to finish the work

- truncate_inode_pages_range

- __filemap_get_folio(, FGP_LOCK) --- lock folio

- truncate_inode_partial_folio

- folio_wait_writeback --- wait on writeback being cleared

- do_garbage_collect

- move_data_page

- f2fs_get_lock_data_folio

- lock on folio --- blocked on folio's lock

In order to avoid such deadlock, let's call below functions to commit

cached bios in GC_MERGE path of f2fs_balance_fs() as the same as we did

in NOGC_MERGE path.

- f2fs_submit_merged_write(sbi, DATA);

- f2fs_submit_all_merged_ipu_writes(sbi);