[PATCH net-next 5/7] net: ipa: skip SKB copy if no netdev

From: Alex Elder
Date: Wed Nov 24 2021 - 15:25:46 EST


In ipa_endpoint_skb_copy(), a new socket buffer structure is
allocated so that some data can be copied into it. However, after
doing this, if the endpoint has a null netdev pointer, we just drop
free the socket buffer.

Instead, check endpoint->netdev pointer first, and just return early
if it's null. Also return early if the SKB allocation fails, to
avoid the deeper indentation in the normal path.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
drivers/net/ipa/ipa_endpoint.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index eeb9f082a0e4c..fba576a7717fa 100644
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -1153,18 +1153,19 @@ static void ipa_endpoint_skb_copy(struct ipa_endpoint *endpoint,
{
struct sk_buff *skb;

+ if (!endpoint->netdev)
+ return;
+
skb = __dev_alloc_skb(len, GFP_ATOMIC);
- if (skb) {
- skb_put(skb, len);
- memcpy(skb->data, data, len);
- skb->truesize += extra;
- }
+ if (!skb)
+ return;

- /* Now receive it, or drop it if there's no netdev */
- if (endpoint->netdev)
- ipa_modem_skb_rx(endpoint->netdev, skb);
- else if (skb)
- dev_kfree_skb_any(skb);
+ /* Copy the data into the socket buffer and receive it */
+ skb_put(skb, len);
+ memcpy(skb->data, data, len);
+ skb->truesize += extra;
+
+ ipa_modem_skb_rx(endpoint->netdev, skb);
}

static bool ipa_endpoint_skb_build(struct ipa_endpoint *endpoint,
--
2.32.0