Subject: [net-next PATCH 04/11] net: ravb: Combine if conditions in RX csum validation

From: Paul Barker <[email-masked]>
Date: Mon, 30 Sep 2024 17:08:38 +0100

From: Paul Barker <[email-masked]>

We can merge the two if conditions on skb_is_nonlinear(). Since
skb_frag_size_sub() and skb_trim() do not free memory, it is still safe
to access the trimmed bytes at the end of the packet after these calls.

Signed-off-by: Paul Barker <[email-masked]>
---
 drivers/net/ethernet/renesas/ravb_main.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index f3913c164161..1dd2152734b0 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -769,18 +769,15 @@ static void ravb_rx_csum_gbeth(struct sk_buff *skb)
 		last_frag = &shinfo->frags[shinfo->nr_frags - 1];
 		hw_csum = skb_frag_address(last_frag) +
 			  skb_frag_size(last_frag);
+		skb_frag_size_sub(last_frag, 2 * sizeof(__sum16));
 	} else {
 		hw_csum = skb_tail_pointer(skb);
+		skb_trim(skb, skb->len - 2 * sizeof(__sum16));
 	}
 
 	hw_csum -= sizeof(__sum16);
 	csum_proto = csum_unfold((__force __sum16)get_unaligned_le16(hw_csum));
 
-	if (skb_is_nonlinear(skb))
-		skb_frag_size_sub(last_frag, 2 * sizeof(__sum16));
-	else
-		skb_trim(skb, skb->len - 2 * sizeof(__sum16));
-
 	if (!csum_proto)
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
 }
-- 
2.43.0