Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Trond Myklebust <trond.myklebust@hammerspace.com>
Subject: [PATCH 4.19 200/271] pnfs/flexfiles: Fix PTR_ERR() dereferences in ff_layout_track_ds_error
Date:   Wed, 24 Jul 2019 21:21:09 +0200
Message-Id: <20190724191712.240675847@linuxfoundation.org>
In-Reply-To: <20190724191655.268628197@linuxfoundation.org>
References: <20190724191655.268628197@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Trond Myklebust <trond.myklebust@hammerspace.com>

commit 8e04fdfadda75a849c649f7e50fe7d97772e1fcb upstream.

mirror->mirror_ds can be NULL if uninitialised, but can contain
a PTR_ERR() if call to GETDEVICEINFO failed.

Fixes: 65990d1afbd2 ("pNFS/flexfiles: Fix a deadlock on LAYOUTGET")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # 4.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/nfs/flexfilelayout/flexfilelayoutdev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -307,7 +307,7 @@ int ff_layout_track_ds_error(struct nfs4
 	if (status == 0)
 		return 0;
 
-	if (mirror->mirror_ds == NULL)
+	if (IS_ERR_OR_NULL(mirror->mirror_ds))
 		return -EINVAL;
 
 	dserr = kmalloc(sizeof(*dserr), gfp_flags);