From:   Jeff Layton <jlayton@kernel.org>
To:     chuck.lever@oracle.com
Cc:     linux-nfs@vger.kernel.org,
        =?UTF-8?q?=E5=BC=B5=E6=99=BA=E8=AB=BA?= <cc85nod@gmail.com>,
        Dai Ngo <dai.ngo@oracle.com>
Subject: [PATCH] nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_open
Date:   Fri,  3 Feb 2023 13:18:34 -0500
Message-Id: <20230203181834.58634-1-jlayton@kernel.org>
MIME-Version: 1.0
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Precedence: bulk

The nested if statements here make no sense, as you can never reach
"else" branch in the nested statement. Fix the error handling for
when there is a courtesy client that holds a conflicting deny mode.

Fixes: 3d69427151806 (NFSD: add support for share reservation conflict to courteous server)
Reported-by: 張智諺 <cc85nod@gmail.com>
Cc: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/nfsd/nfs4state.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index c39e43742dd6..af22dfdc6fcc 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -5282,16 +5282,17 @@ nfs4_upgrade_open(struct svc_rqst *rqstp, struct nfs4_file *fp,
 	/* test and set deny mode */
 	spin_lock(&fp->fi_lock);
 	status = nfs4_file_check_deny(fp, open->op_share_deny);
-	if (status == nfs_ok) {
-		if (status != nfserr_share_denied) {
-			set_deny(open->op_share_deny, stp);
-			fp->fi_share_deny |=
-				(open->op_share_deny & NFS4_SHARE_DENY_BOTH);
-		} else {
-			if (nfs4_resolve_deny_conflicts_locked(fp, false,
-					stp, open->op_share_deny, false))
-				status = nfserr_jukebox;
-		}
+	switch (status) {
+	case nfs_ok:
+		set_deny(open->op_share_deny, stp);
+		fp->fi_share_deny |=
+			(open->op_share_deny & NFS4_SHARE_DENY_BOTH);
+		break;
+	case nfserr_share_denied:
+		if (nfs4_resolve_deny_conflicts_locked(fp, false,
+				stp, open->op_share_deny, false))
+			status = nfserr_jukebox;
+		break;
 	}
 	spin_unlock(&fp->fi_lock);
 
-- 
2.39.1