From: Wei Yongjun <weiyongjun1@xxxxxxxxxx> [ Upstream commit 297a6961ffb8ff4dc66c9fbf53b924bd1dda05d5 ] platform_get_resource() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference a bit later in the code. This is detected by Coccinelle semantic patch. @@ expression pdev, res, n, t, e, e1, e2; @@ res = platform_get_resource(pdev, t, n); + if (!res) + return -EINVAL; ... when != res == NULL e = devm_ioremap(e1, res->start, e2); Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/phy/mdio-bcm-unimac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/phy/mdio-bcm-unimac.c b/drivers/net/phy/mdio-bcm-unimac.c index 4bde5e728fe0a..fd8692b477c96 100644 --- a/drivers/net/phy/mdio-bcm-unimac.c +++ b/drivers/net/phy/mdio-bcm-unimac.c @@ -177,6 +177,8 @@ static int unimac_mdio_probe(struct platform_device *pdev) return -ENOMEM; r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) + return -EINVAL; /* Just ioremap, as this MDIO block is usually integrated into an * Ethernet MAC controller register range -- 2.25.1