drivers/net: process the result of hdlc_open() and add call of hdlc_close() in uhdlc_...

[ Upstream commit a59addacf899b1b21a7b7449a1c52c98704c2472 ]

Process the result of hdlc_open() and call uhdlc_close()
in case of an error. It is necessary to pass the error
code up the control flow, similar to a possible
error in request_irq().
Also add a hdlc_close() call to the uhdlc_close()
because the comment to hdlc_close() says it must be called
by the hardware driver when the HDLC device is being closed

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: c19b6d246a35 ("drivers/net: support hdlc function for QE-UCC")
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
index 978f642dacedd3c65fda04d1205ba6788b14d4b2..00cc9b755a85270ddaaba038b231debd43002390 100644 (file)
--- a/drivers/net/wan/fsl_ucc_hdlc.c
+++ b/drivers/net/wan/fsl_ucc_hdlc.c
@@ -37,6 +37,8 @@
 
 #define TDM_PPPOHT_SLIC_MAXIN
 
+static int uhdlc_close(struct net_device *dev);
+
 static struct ucc_tdm_info utdm_primary_info = {
        .uf_info = {
                .tsa = 0,
@@ -662,6 +664,7 @@ static int uhdlc_open(struct net_device *dev)
        hdlc_device *hdlc = dev_to_hdlc(dev);
        struct ucc_hdlc_private *priv = hdlc->priv;
        struct ucc_tdm *utdm = priv->utdm;
+       int rc = 0;
 
        if (priv->hdlc_busy != 1) {
                if (request_irq(priv->ut_info->uf_info.irq,
@@ -684,10 +687,13 @@ static int uhdlc_open(struct net_device *dev)
                netif_device_attach(priv->ndev);
                napi_enable(&priv->napi);
                netif_start_queue(dev);
-               hdlc_open(dev);
+
+               rc = hdlc_open(dev);
+               if (rc)
+                       uhdlc_close(dev);
        }
 
-       return 0;
+       return rc;
 }
 
 static void uhdlc_memclean(struct ucc_hdlc_private *priv)
@@ -776,6 +782,8 @@ static int uhdlc_close(struct net_device *dev)
        netif_stop_queue(dev);
        priv->hdlc_busy = 0;
 
+       hdlc_close(dev);
+
        return 0;
 }