Re: [PATCH] net: handle the return value of pskb_carve_frag_list() correctly

[David Miller]

From: linmiaohe <linmiaohe@xxxxxxxxxx>
Date: Mon, 17 Aug 2020 02:27:23 +0000

> David Miller <davem@xxxxxxxxxxxxx> wrote:
>>> +	/* split line is in frag list */
>>> +	if (k == 0 && pskb_carve_frag_list(skb, shinfo, off - pos, gfp_mask)) {
>>> +		/* skb_frag_unref() is not needed here as shinfo->nr_frags = 0. */
>>> +		if (skb_has_frag_list(skb))
>>> +			kfree_skb_list(skb_shinfo(skb)->frag_list);
>>> +		kfree(data);
>>> +		return -ENOMEM;
>>
>>On error, the caller is going to kfree_skb(skb) which will take care of the frag list.
>>
> 
> I'am sorry for my careless. The caller will take care of the frag list and kfree(data) is enough here.
> Many thanks for review, will send v2 soon.

Actually, reading this again, what about the skb_clone_fraglist() done a few
lines up?  Who will release that reference to the fraglist items?

Maybe the kfree_skb_list() is necessary after all?