net: nla_align_64bit() needs to test the right pointer.

Netlink messages are appended, one object at a time, to the end of
the SKB.  Therefore we need to test skb_tail_pointer() not skb->data
for alignment.

Fixes: 35c5845957 ("net: Add helpers for 64-bit aligning netlink attributes.")
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2016-04-20 15:32:54 -04:00
parent cca1d81574
commit e6f268ef36

View File

@ -1250,7 +1250,7 @@ static inline int nla_align_64bit(struct sk_buff *skb, int padattr)
* nlattr header for next attribute, will make nla_data()
* 8-byte aligned.
*/
if (IS_ALIGNED((unsigned long)skb->data, 8) &&
if (IS_ALIGNED((unsigned long)skb_tail_pointer(skb), 8) &&
!nla_reserve(skb, padattr, 0))
return -EMSGSIZE;
#endif