d8b8a41918
(1.44) missed a test for the right interface, making some machines answer to some bogus arp requests (like for WHO-HAS 127.0.0.1). The quick patch in 1.46-1.47 does not work for so-called "unnumbered" interfaces, that is, (point-to-point) interfaces that share their local address with another (e.g., the Ethernet) interface. We add a macro to in_var.h, to step (in the current implementation) through the hash chain and fine more entries with the same address, and use that in if_arp.c to find one which belongs to our interface.