[Bug 383525] [NEW] SOCK_RAW does not receive broadcast (with VLAN unless PROMISC)

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Dear Linux Experts,

My application is using PF_PACKET and SOCK_RAW in order to receive all
Ethernet packets for the machine-unicast MAC plus all broadcast packets
(like ARP broadcast).

That worked OK with kernel 2.6.20 (Ubuntu 7.04 with or without VLAN).

Now with kernel 2.6.28 (Ubuntu 9.04) it works OK only without-VLAN, but
with VLAN the application receive only packets for the machine-unicast
MAC, but no broadcast (like ARP broadcast) packets, only if I set the
socket to PROMISC mode, I start receive also broadcast packets.

To me it seems a bug, as SOCK_RAW should pass all ‘received’ packet
(including broadcast) to the application, without the need for PROMISC
(which cause my machine to receive other machine unicast  packets, and
filter those by software)!

The original application:

sock=socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
memset((char *) &sockad, 0, sizeof(sockad));
sockad.sll_family = PF_PACKET;
sockad.sll_protocol = htons(ETH_P_ALL);
sockad.sll_ifindex = ethreq.ifr_ifindex;//the relevant unit number


Now the workaround is to set (unwanted) PROMISC mode:

ioctl(sock,SIOCGIFFLAGS,&ethreq);
ethreq.ifr_flags|=IFF_PROMISC; // why does 9.04 need this (+0x100) at least once?!
ioctl(sock,SIOCSIFFLAGS,&ethreq);

 
Many thanks in advance,
Gil Beniamini
gil.beniamini at gmail.com

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 9.04
ExecutablePath: /usr/bin/yelp
Package: yelp 2.25.1-0ubuntu5
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: yelp
Uname: Linux 2.6.28-11-generic i686

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: apport-bug i386
-- 
SOCK_RAW does not receive broadcast (with VLAN unless PROMISC)
https://bugs.launchpad.net/bugs/383525
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