brcmfmac: check ndev pointer

[ Upstream commit 9c9f015bc9f8839831c7ba0a6d731a3853c464e2 ]

Clang static analysis reports this error

brcmfmac/core.c:490:4: warning: Dereference of null pointer
        (*ifp)->ndev->stats.rx_errors++;
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In this block of code

	if (ret || !(*ifp) || !(*ifp)->ndev) {
		if (ret != -ENODATA && *ifp)
			(*ifp)->ndev->stats.rx_errors++;
		brcmu_pkt_buf_free_skb(skb);
		return -ENODATA;
	}

(*ifp)->ndev being NULL is caught as an error
But then it is used to report the error.

So add a check before using it.

Fixes: 91b632803ee4 ("brcmfmac: Use net_device_stats from struct net_device")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200802161804.6126-1-trix@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index c88655acc78c7a27d00e8d17fad18ea50ea01577..76b478f70b4bb7d774c70f4cebb0e91a0969476c 100644 (file)
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -483,7 +483,7 @@ static int brcmf_rx_hdrpull(struct brcmf_pub *drvr, struct sk_buff *skb,
        ret = brcmf_proto_hdrpull(drvr, true, skb, ifp);
 
        if (ret || !(*ifp) || !(*ifp)->ndev) {
-               if (ret != -ENODATA && *ifp)
+               if (ret != -ENODATA && *ifp && (*ifp)->ndev)
                        (*ifp)->ndev->stats.rx_errors++;
                brcmu_pkt_buf_free_skb(skb);
                return -ENODATA;