Author: Trond Myklebust NLM: Ensure we do not Oops in the case of an unlock In theory, NLM specs assure us that the server will only reply LCK_GRANTED or LCK_DENIED_GRACE_PERIOD to our NLM_UNLOCK request. In practice, we should not assume this to be the case, and the code will currently Oops if we do. Signed-off-by: Trond Myklebust --- fs/lockd/clntproc.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index 220058d..970b6a6 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -662,12 +662,18 @@ nlmclnt_unlock(struct nlm_rqst *req, str * reclaimed while we're stuck in the unlock call. */ fl->fl_u.nfs_fl.flags &= ~NFS_LCK_GRANTED; + /* + * Note: the server is supposed to either grant us the unlock + * request, or to deny it with NLM_LCK_DENIED_GRACE_PERIOD. In either + * case, we want to unlock. + */ + do_vfs_lock(fl); + if (req->a_flags & RPC_TASK_ASYNC) { status = nlmclnt_async_call(req, NLMPROC_UNLOCK, &nlmclnt_unlock_ops); /* Hrmf... Do the unlock early since locks_remove_posix() * really expects us to free the lock synchronously */ - do_vfs_lock(fl); if (status < 0) { nlmclnt_release_lockargs(req); kfree(req); @@ -680,7 +686,6 @@ nlmclnt_unlock(struct nlm_rqst *req, str if (status < 0) return status; - do_vfs_lock(fl); if (resp->status == NLM_LCK_GRANTED) return 0;