Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - nfs: fix NULL deference in nfs4_get_valid_delegation

  Bugfixes:
   - Fix corruption of the return value in cachefiles_read_or_alloc_pages()
   - Fix several fscache cookie issues
   - Fix a fscache queuing race that can trigger a BUG_ON
   - NFS: Fix two use-after-free regressions due to the RPC_TASK_CRED_NOREF flag
   - SUNRPC: Fix a use-after-free regression in rpc_free_client_work()
   - SUNRPC: Fix a race when tearing down the rpc client debugfs directory
   - SUNRPC: Signalled ASYNC tasks need to exit
   - NFSv3: fix rpc receive buffer size for MOUNT call"

* tag 'nfs-for-5.7-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv3: fix rpc receive buffer size for MOUNT call
  SUNRPC: 'Directory with parent 'rpc_clnt' already present!'
  NFS/pnfs: Don't use RPC_TASK_CRED_NOREF with pnfs
  NFS: Don't use RPC_TASK_CRED_NOREF with delegreturn
  SUNRPC: Signalled ASYNC tasks need to exit
  nfs: fix NULL deference in nfs4_get_valid_delegation
  SUNRPC: fix use-after-free in rpc_free_client_work()
  cachefiles: Fix race between read_waiter and read_copier involving op->to_do
  NFSv4: Fix fscache cookie aux_data to ensure change_attr is included
  NFS: Fix fscache super_cookie allocation
  NFS: Fix fscache super_cookie index_key from changing after umount
  cachefiles: Fix corruption of the return value in cachefiles_read_or_alloc_pages()