| Message ID | 20241105174403.850330-7-edumazet@google.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: add debug checks to skb_reset_xxx_header() | expand |
On Tue, Nov 05, 2024 at 05:44:02PM +0000, Eric Dumazet wrote: > Make sure (skb->data - skb->head) can fit in skb->network_header > > This needs CONFIG_DEBUG_NET=y. > > Signed-off-by: Eric Dumazet <edumazet@google.com> > --- > include/linux/skbuff.h | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) Reviewed-by: Joe Damato <jdamato@fastly.com>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index f76524844e7edc5fe4e0afc27ce71eed7fbd40f9..f1e49a32880df8f3716c585d13c1085a2183978a 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3027,7 +3027,10 @@ static inline unsigned char *skb_network_header(const struct sk_buff *skb) static inline void skb_reset_network_header(struct sk_buff *skb) { - skb->network_header = skb->data - skb->head; + long offset = skb->data - skb->head; + + DEBUG_NET_WARN_ON_ONCE(offset != (typeof(skb->network_header))offset); + skb->network_header = offset; } static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
Make sure (skb->data - skb->head) can fit in skb->network_header This needs CONFIG_DEBUG_NET=y. Signed-off-by: Eric Dumazet <edumazet@google.com> --- include/linux/skbuff.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)