CVE-2025-39842

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

ocfs2: prevent release journal inode after journal shutdown

Before calling ocfs2_delete_osb(), ocfs2_journal_shutdown() has already
been executed in ocfs2_dismount_volume(), so osb->journal must be NULL.
Therefore, the following calltrace will inevitably fail when it reaches
jbd2_journal_release_jbd_inode().

ocfs2_dismount_volume()->
ocfs2_delete_osb()->
ocfs2_free_slot_info()->
__ocfs2_free_slot_info()->
evict()->
ocfs2_evict_inode()->
ocfs2_clear_inode()->
jbd2_journal_release_jbd_inode(osb->journal->j_journal,

Adding osb->journal checks will prevent null-ptr-deref during the above
execution path.

More information : https://git.kernel.org/stable/c/42c415c53ad2065088cc411d08925effa5b3d255