Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:  nfsd: clear CALLBACK_RUNNING on failed delegation recall queue  nfsd_break_one_deleg() sets NFSD4_CALLBACK_RUNNING via test_and_set_bit at entry to serialize recall work, then calls nfsd4_run_cb() to queue the recall.  When the queue attempt fails the refcount bump is undone, but the RUNNING bit is left set.  The only site that clears the bit is nfsd41_destroy_cb() (fs/nfsd/nfs4callback.c), which runs from the workqueue and is therefore unreachable when nothing was queued.  The bit becomes a permanent latch on dp->dl_recall.cb_flags: every subsequent break_lease() on the same delegation hits the early-return guard in nfsd_break_one_deleg() and silently skips the recall, so the delegation is never broken and the conflicting open or lock stalls.  Fix by clearing NFSD4_CALLBACK_RUNNING on the !queued branch alongside the refcount_dec.