Commit c123e0d3 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: add truesize debug checks in skb_{add|coalesce}_rx_frag() 



It can be time consuming to track driver bugs, that might be detected
too late from this confusing warning in skb_try_coalesce()

	WARN_ON_ONCE(delta < len);

Add sanity check in skb_add_rx_frag() and skb_coalesce_rx_frag()
to better track bug origin for CONFIG_DEBUG_NET=y builds.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 41862d12

net/core/skbuff.c

+4 −0
Original line number Diff line number Diff line
@@ -847,6 +847,8 @@ EXPORT_SYMBOL(__napi_alloc_skb); 
void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off,

		     int size, unsigned int truesize)

{

	DEBUG_NET_WARN_ON_ONCE(size > truesize);



	skb_fill_page_desc(skb, i, page, off, size);

	skb->len += size;

	skb->data_len += size;
@@ -859,6 +861,8 @@ void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, 
{

	skb_frag_t *frag = &skb_shinfo(skb)->frags[i];



	DEBUG_NET_WARN_ON_ONCE(size > truesize);



	skb_frag_size_add(frag, size);

	skb->len += size;

	skb->data_len += size;