Bug 29962

Summary:

sent broadcast packets get spurious 4 byte prefix

Product:

Base System

Reporter:

kolya <kolya>

Component:

kern

Assignee:

freebsd-bugs (Nobody) <bugs>

Status:

Closed FIXED

Severity:

Affects Only Me

Priority:

Normal

Version:

4.3-STABLE

Hardware:

Any

OS:

Any

Attachments:

Description	Flags
file.diff	none

Description kolya 2001-08-22 20:10:01 UTC

	Sending a broadcast packet on an ethernet interface while watching
	the traffic via bpf with tcpdump produces a spurious 4-byte prefix
	on the broadcast packet (as observed with tcpdump, not on the wire.)

Fix: This simple patch fixes the problem; as far as I can tell, the
	comment is wrong, though I don't claim to be very familiar with
	this code.
How-To-Repeat: 
	ifconfig fxp0 1.0.0.1
	tcpdump -e -n -x -s 1600 -i fxp0 &
	ping -c 1 1.255.255.255

	As seen in the tcpdump output, an extra 4 bytes are prepended to
	the broadcast IP packet, containing the value 0x02000000.

Comment 1 dd freebsd_committer

2001-08-28 13:21:09 UTC

Responsible Changed
From-To: gnats-admin->freebsd-bugs

refile

Comment 2 Maxim Konovalov freebsd_committer

2002-10-28 16:01:04 UTC

State Changed
From-To: open->closed

Fixed in rev. 1.61 and rev. 1.47.2.5 src/sys/net/if_loop.c in 
-CURRENT and -STABLE. Thanks for the report.