lockd: nlmclnt_reclaim(): avoid stack overflow

Even though nlmclnt_reclaim() is only one call into the stack frame,
928 bytes on the stack seems like a lot. Recode to dynamically
allocate the request structure once from within the reclaimer task,
then pass this pointer into nlmclnt_reclaim() for reuse on
subsequent calls.

smatch analysis:

fs/lockd/clntproc.c:620 nlmclnt_reclaim() warn: 'reqst' puts
 928 bytes on stack

Also remove redundant assignment of 0 after memset.

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index f5a051a79273..a395f1e7998f 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -212,7 +212,8 @@ int		  nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout)
 __be32            nlmclnt_grant(const struct sockaddr *addr,
                                 const struct nlm_lock *lock);
 void              nlmclnt_recovery(struct nlm_host *);
-int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *);
+int               nlmclnt_reclaim(struct nlm_host *, struct file_lock *,
+                                  struct nlm_rqst *);
 void              nlmclnt_next_cookie(struct nlm_cookie *);
 
 /*