ipv4: arp: update neighbour address when a gratuitous arp is received and arp_accept is set
Gratuitous arp packets are useful in switchover scenarios to update client arp tables as quickly as possible. Currently, the mac address of a neighbour is only updated after a locktime period has elapsed since the last update. In most use cases such delays are unacceptable for network admins. Moreover, the "updated" field of the neighbour stucture doesn't record the last time the address of a neighbour changed but records any change that happens to the neighbour. This is clearly a bug since locktime uses that field as meaning "addr_updated". With this observation, I was able to perpetuate a stale address by sending a stream of gratuitous arp packets spaced less than locktime apart. With this change the address is updated when a gratuitous arp is received and the arp_accept sysctl is set. Signed-off-by:Salam Noureddine <noureddine@aristanetworks.com> Acked-by:
Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
e8243534
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