[PATCH v3] net: stmmac: fix maxmtu assignment to be within valid range
From: Kweh, Hock Leong
Date: Fri Jan 06 2017 - 11:44:20 EST
From: "Kweh, Hock Leong" <hock.leong.kweh@xxxxxxxxx>
There is no checking valid value of maxmtu when getting it from device tree.
This resolution added the checking condition to ensure the assignment is
made within a valid range.
Signed-off-by: Kweh, Hock Leong <hock.leong.kweh@xxxxxxxxx>
---
changelog v3:
* print the warning message only if maxmtu < min_mtu
* add maxmtu = JUMBO_LEN at stmmac_pci.c to follow stmmac_platform.c
changelog v2:
* correction of "devicetree" to "device tree" reported by Andy
* print warning message while maxmtu is not in valid range
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 8 +++++++-
drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c | 4 ++++
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 92ac006..ce74ae6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3345,8 +3345,14 @@ int stmmac_dvr_probe(struct device *device,
ndev->max_mtu = JUMBO_LEN;
else
ndev->max_mtu = SKB_MAX_HEAD(NET_SKB_PAD + NET_IP_ALIGN);
- if (priv->plat->maxmtu < ndev->max_mtu)
+
+ if ((priv->plat->maxmtu < ndev->max_mtu) &&
+ (priv->plat->maxmtu >= ndev->min_mtu))
ndev->max_mtu = priv->plat->maxmtu;
+ else if (priv->plat->maxmtu < ndev->min_mtu)
+ netdev_warn(priv->dev,
+ "%s: warning: maxmtu having invalid value (%d)\n",
+ __func__, priv->plat->maxmtu);
if (flow_ctrl)
priv->flow_ctrl = FLOW_AUTO; /* RX/TX pause on */
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
index a283177..e539afe 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
@@ -204,6 +204,10 @@ static int stmmac_pci_probe(struct pci_dev *pdev,
pci_set_master(pdev);
+ /* Set the maxmtu to a default of JUMBO_LEN in case the
+ * parameter is not defined for the device.
+ */
+ plat->maxmtu = JUMBO_LEN;
if (info) {
info->pdev = pdev;
if (info->setup) {
--
1.7.9.5