From 34b09af4f54e6485e28f138ccad159611a240cc1 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Wed, 5 Aug 2020 15:10:11 -0400
Subject: [PATCH 1/2] nfsd: fix oops on mixed NFSv4/NFSv3 client access

If an NFSv2/v3 client breaks an NFSv4 client's delegation, it will hit a
NULL dereference in nfsd_breaker_owns_lease().

Easily reproduceable with for example

	mount -overs=4.2 server:/export /mnt/
	sleep 1h </mnt/file &
	mount -overs=3 server:/export /mnt2/
	touch /mnt2/file

Reported-by: Robert Dinse <nanook@eskimo.com>
Fixes: 28df3d1539de50 ("nfsd: clients don't need to break their own delegations")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=208807
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4state.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 81ed8e8bab3f..1ea9bbcc7c24 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -4597,6 +4597,8 @@ static bool nfsd_breaker_owns_lease(struct file_lock *fl)
 	if (!i_am_nfsd())
 		return NULL;
 	rqst = kthread_data(current);
+	if (!rqst->rq_lease_breaker)
+		return NULL;
 	clp = *(rqst->rq_lease_breaker);
 	return dl->dl_stid.sc_client == clp;
 }

From ad112aa8b1ac4bf5e8da67734fcb535fd3cd564e Mon Sep 17 00:00:00 2001
From: Wang Hai <wanghai38@huawei.com>
Date: Wed, 19 Aug 2020 10:49:43 +0800
Subject: [PATCH 2/2] SUNRPC: remove duplicate include

Remove linux/sunrpc/auth_gss.h which is included more than once

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 net/sunrpc/auth_gss/trace.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/sunrpc/auth_gss/trace.c b/net/sunrpc/auth_gss/trace.c
index d26036a57443..76685abba60f 100644
--- a/net/sunrpc/auth_gss/trace.c
+++ b/net/sunrpc/auth_gss/trace.c
@@ -9,7 +9,6 @@
 #include <linux/sunrpc/svc_xprt.h>
 #include <linux/sunrpc/auth_gss.h>
 #include <linux/sunrpc/gss_err.h>
-#include <linux/sunrpc/auth_gss.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/rpcgss.h>