[PATCH 04/19] staging: ks7010: move skb null check near allocation

Tobin C. Harding me at tobin.cc
Wed Apr 26 00:55:09 UTC 2017


Currently, after allocating an sk_buff, driver fills the sk_buff
within code block guarded by a NULL check on the sk_buff. If a NULL
check is done immediately after the allocation, and code returns on
error, then the subsequent code need not be guarded and the level of
indentation may be reduced. This aids the readability of the code and
makes explicit the error path.

Check for NULL directly after allocating the sk_buff, return if
allocation fails. Reduce indentation of subsequent code. Do not change
the program logic.

Signed-off-by: Tobin C. Harding <me at tobin.cc>
---
 drivers/staging/ks7010/ks_hostif.c | 80 ++++++++++++++++++++------------------
 1 file changed, 42 insertions(+), 38 deletions(-)

diff --git a/drivers/staging/ks7010/ks_hostif.c b/drivers/staging/ks7010/ks_hostif.c
index fab3afe..11adc5f 100644
--- a/drivers/staging/ks7010/ks_hostif.c
+++ b/drivers/staging/ks7010/ks_hostif.c
@@ -446,56 +446,60 @@ void hostif_data_indication(struct ks_wlan_private *priv)
 	case 0xAA:	/* SNAP */
 		rx_ind_size = priv->rx_size - 6;
 		skb = dev_alloc_skb(rx_ind_size);
-		DPRINTK(4, "SNAP, rx_ind_size = %d\n", rx_ind_size);
-
-		if (skb) {
-			memcpy(skb_put(skb, 12), priv->rxp, 12);	/* 8802/FDDI MAC copy */
-			/* (SNAP+UI..) skip */
-			memcpy(skb_put(skb, rx_ind_size - 12), priv->rxp + 18, rx_ind_size - 12);	/* copy after Type */
-
-			aa1x_hdr = (struct ieee802_1x_hdr *)(priv->rxp + 20);
-			if (aa1x_hdr->type == IEEE802_1X_TYPE_EAPOL_KEY &&
-			    priv->wpa.rsn_enabled)
-				atomic_set(&priv->psstatus.snooze_guard, 1);
-
-			/* rx indication */
-			skb->dev = priv->net_dev;
-			skb->protocol = eth_type_trans(skb, skb->dev);
-			priv->nstats.rx_packets++;
-			priv->nstats.rx_bytes += rx_ind_size;
-			netif_rx(skb);
-		} else {
+		if (!skb) {
 			priv->nstats.rx_dropped++;
+			return;
 		}
+		DPRINTK(4, "SNAP, rx_ind_size = %d\n", rx_ind_size);
+
+		memcpy(skb_put(skb, 12), priv->rxp, 12);	/* 8802/FDDI MAC copy */
+		/* (SNAP+UI..) skip */
+		memcpy(skb_put(skb, rx_ind_size - 12), priv->rxp + 18,
+		       rx_ind_size - 12);	/* copy after Type */
+
+		aa1x_hdr = (struct ieee802_1x_hdr *)(priv->rxp + 20);
+		if (aa1x_hdr->type == IEEE802_1X_TYPE_EAPOL_KEY &&
+		    priv->wpa.rsn_enabled)
+			atomic_set(&priv->psstatus.snooze_guard, 1);
+
+		/* rx indication */
+		skb->dev = priv->net_dev;
+		skb->protocol = eth_type_trans(skb, skb->dev);
+		priv->nstats.rx_packets++;
+		priv->nstats.rx_bytes += rx_ind_size;
+		netif_rx(skb);
+
 		break;
 	case 0xF0:	/* NETBEUI/NetBIOS */
 		rx_ind_size = (priv->rx_size + 2);
 		skb = dev_alloc_skb(rx_ind_size);
+		if (!skb) {
+			priv->nstats.rx_dropped++;
+			return;
+		}
 		DPRINTK(3, "NETBEUI/NetBIOS rx_ind_size=%d\n", rx_ind_size);
 
-		if (skb) {
-			memcpy(skb_put(skb, 12), priv->rxp, 12);	/* 8802/FDDI MAC copy */
+		memcpy(skb_put(skb, 12), priv->rxp, 12);	/* 8802/FDDI MAC copy */
 
-			temp[0] = (((rx_ind_size - 12) >> 8) & 0xff);	/* NETBEUI size add */
-			temp[1] = ((rx_ind_size - 12) & 0xff);
-			memcpy(skb_put(skb, 2), temp, 2);
+		temp[0] = (((rx_ind_size - 12) >> 8) & 0xff);	/* NETBEUI size add */
+		temp[1] = ((rx_ind_size - 12) & 0xff);
+		memcpy(skb_put(skb, 2), temp, 2);
 
-			memcpy(skb_put(skb, rx_ind_size - 14), priv->rxp + 12, rx_ind_size - 14);	/* copy after Type */
+		memcpy(skb_put(skb, rx_ind_size - 14), priv->rxp + 12,
+		       rx_ind_size - 14);	/* copy after Type */
 
-			aa1x_hdr = (struct ieee802_1x_hdr *)(priv->rxp + 14);
-			if (aa1x_hdr->type == IEEE802_1X_TYPE_EAPOL_KEY &&
-			    priv->wpa.rsn_enabled)
-				atomic_set(&priv->psstatus.snooze_guard, 1);
+		aa1x_hdr = (struct ieee802_1x_hdr *)(priv->rxp + 14);
+		if (aa1x_hdr->type == IEEE802_1X_TYPE_EAPOL_KEY &&
+		    priv->wpa.rsn_enabled)
+			atomic_set(&priv->psstatus.snooze_guard, 1);
+
+		/* rx indication */
+		skb->dev = priv->net_dev;
+		skb->protocol = eth_type_trans(skb, skb->dev);
+		priv->nstats.rx_packets++;
+		priv->nstats.rx_bytes += rx_ind_size;
+		netif_rx(skb);
 
-			/* rx indication */
-			skb->dev = priv->net_dev;
-			skb->protocol = eth_type_trans(skb, skb->dev);
-			priv->nstats.rx_packets++;
-			priv->nstats.rx_bytes += rx_ind_size;
-			netif_rx(skb);
-		} else {
-			priv->nstats.rx_dropped++;
-		}
 		break;
 	default:	/* other rx data */
 		DPRINTK(2, "invalid data format\n");
-- 
2.7.4



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