[PATCH v2] fsl_ucc_hdlc: add a check of the return value from hdlc_open

From: Alexandra Diupina
Date: Mon Aug 28 2023 - 04:28:31 EST


Process the result of hold_open() and return it from
uhdlc_open() 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()

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>
---
v2: Remove the 'rc' variable (stores the return value of the
hdlc_open()) as Christophe Leroy <christophe.leroy@xxxxxxxxxx> suggested
drivers/net/wan/fsl_ucc_hdlc.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
index cdd9489c712e..4164abea7725 100644
--- a/drivers/net/wan/fsl_ucc_hdlc.c
+++ b/drivers/net/wan/fsl_ucc_hdlc.c
@@ -708,7 +708,6 @@ 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,
@@ -732,12 +731,10 @@ static int uhdlc_open(struct net_device *dev)
napi_enable(&priv->napi);
netdev_reset_queue(dev);
netif_start_queue(dev);
- rc = hdlc_open(dev);
- if (rc)
- return rc;
+ return hdlc_open(dev);
}

- return rc;
+ return 0;
}

static void uhdlc_memclean(struct ucc_hdlc_private *priv)
--
2.30.2