From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Fri, 19 Jul 2019 17:48:44 +0000 (-0400)
Subject: NFSv4: Fix a credential refcount leak in nfs41_check_delegation_stateid
X-Git-Tag: v5.2.11~94
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=8c0391db53efffb30913c06367f1b3793fc3ba18;p=users%2Fdwmw2%2Flinux.git

NFSv4: Fix a credential refcount leak in nfs41_check_delegation_stateid

[ Upstream commit 8c39a39e28b86a4021d9be314ce01019bafa5fdc ]

It is unsafe to dereference delegation outside the rcu lock, and in
any case, the refcount is guaranteed held if cred is non-zero.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 63edda145d1b8..420f2350c2781 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2752,8 +2752,7 @@ static void nfs41_check_delegation_stateid(struct nfs4_state *state)
 	if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID)
 		nfs_finish_clear_delegation_stateid(state, &stateid);
 
-	if (delegation->cred)
-		put_cred(cred);
+	put_cred(cred);
 }
 
 /**