NFS: Fix a use after free in nfs_direct_join_group()

stable inclusion
from stable-v5.10.193
commit 7c262127d264f28fca52351226d182eeb553abc9
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9399M

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7c262127d264f28fca52351226d182eeb553abc9



--------------------------------

commit be2fd156 upstream.

Be more careful when tearing down the subrequests of an O_DIRECT write
as part of a retransmission.

Reported-by: Chris Mason <clm@fb.com>
Fixes: ed5d588f ("NFS: Try to join page groups before an O_DIRECT retransmission")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>