Patch "drivers/net: process the result of hdlc_open() and add call of hdlc_close() in uhdlc_close()" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

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

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drivers-net-process-the-result-of-hdlc_open-and-add-.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 1f4600c7384cea9e5e866d1961c9bac6ea5bef22
Author: Alexandra Diupina <adiupina@xxxxxxxxxxxxx>
Date:   Tue Sep 19 17:25:02 2023 +0300

    drivers/net: process the result of hdlc_open() and add call of hdlc_close() in uhdlc_close()
    
    [ 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@xxxxxxxxxxxxx>
    Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
    Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
index 46077cef855b2..8a0c2ea03ff9c 100644
--- a/drivers/net/wan/fsl_ucc_hdlc.c
+++ b/drivers/net/wan/fsl_ucc_hdlc.c
@@ -34,6 +34,8 @@
 #define TDM_PPPOHT_SLIC_MAXIN
 #define RX_BD_ERRORS (R_CD_S | R_OV_S | R_CR_S | R_AB_S | R_NO_S | R_LG_S)
 
+static int uhdlc_close(struct net_device *dev);
+
 static struct ucc_tdm_info utdm_primary_info = {
 	.uf_info = {
 		.tsa = 0,
@@ -710,6 +712,7 @@ 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,
@@ -733,10 +736,13 @@ static int uhdlc_open(struct net_device *dev)
 		napi_enable(&priv->napi);
 		netdev_reset_queue(dev);
 		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)
@@ -826,6 +832,8 @@ static int uhdlc_close(struct net_device *dev)
 	netdev_reset_queue(dev);
 	priv->hdlc_busy = 0;
 
+	hdlc_close(dev);
+
 	return 0;
 }