field. This returns the sdl_data field to a variable-length field. More
importantly, this prevents a easily-reproduceable data-corruption bug when
the interface name plus the hardware address exceed the sdl_data field's
original 12 byte limit. However, token-ring interfaces may still overflow
the new sdl_data field's 46 byte limit if the interface name exceeds 6
characters (since 6 characters for interface name plus 6 for hardware
address plus 34 for source routing = the size of sdl_data). Further
refinements could overcome this limitation but would break binary
compatibility; this commit only addresses fixing the bug for
commonly-occuring cases without breaking binary compatibility with the
intention that the functionality can be MFC'ed to -stable.
See message ID's (both send to -arch):
20020421013332.F87395-100000@gateway.posi.net20020430181359.G11009-300000@gateway.posi.net
for a more thorough description of the bug addressed and how to
reproduce it.
Approved by: silence on -arch and -net
Sponsored by: NTT Multimedia Communications Labs
MFC after: 1 week
42fdfc126a