Patch-ID# 100045-01
Keywords:	icmp netmask broadcast network subnet subnetting mask
Synopsis:Spurious netmask replies set wrong subnet mask.
Date: 19-Dec-89

SunOS release:
	4.0.3

Bug ID's fixed with this patch:
	1017292

Patches which conflict with this patch:

Architectures for which this patch is available:
	sun3, sun3x, sun4, sun4c, sun386

Obsoleted by:
	4.1

Problem description:

	When a Sun machine receives a broadcast netmask reply, it sets
	the netmask accordingly.  However, if the reply contains an
	incorrect subnet mask, the result will overwrite the original
	correct one.  This patch will cause such packets to be ignored.
	A new kernel module (ip_icmp.o) is included in this patch; this
	new version will prevent the Sun from resetting the subnet value
	when these unexpected packets are received.