Re: [PATCH net-next] net: arp: use kfree_skb_reason() in arp_rcv()

From: jiang.kun2
Date: Mon May 26 2025 - 07:47:31 EST


>Are these errors common enough to get dedicated drop reasons ? Most
>stacks have implemented ARP more than 20 years ago.
>
>I think that for rare events like this, the standard call graph should
>be plenty enough. (perf record -ag -e skb:kfree_skb)
>
>Otherwise we will get 1000 drop reasons, and the profusion of names
>makes them useless.

Thank you for your feedback.

Maliciously crafted ARP packets often trigger these two scenarios. 
Using perf cannot directly distinguish between the two cases; 
additionally, enabling perf in embedded environments may lead to 
noticeable performance overhead.

More importantly, in this patch, I believe replacing pskb_may_pull with 
pskb_may_pull_reason makes sense, so using kfree_skb_reason() in 
arp_rcv() is meaningful.