Simon Kelley bd89efc532 [NEIGH]: Fix IP-over-ATM and ARP interaction. ... The classical IP over ATM code maintains its own IPv4 <-> <ATM stuff> ARP table, using the standard neighbour-table code. The neigh_table_init function adds this neighbour table to a linked list of all neighbor tables which is used by the functions neigh_delete() neigh_add() and neightbl_set(), all called by the netlink code. Once the ATM neighbour table is added to the list, there are two tables with family == AF_INET there, and ARP entries sent via netlink go into the first table with matching family. This is indeterminate and often wrong. To see the bug, on a kernel with CLIP enabled, create a standard IPv4 ARP entry by pinging an unused address on a local subnet. Then attempt to complete that entry by doing ip neigh replace <ip address> lladdr <some mac address> nud reachable Looking at the ARP tables by using ip neigh show will reveal two ARP entries for the same address. One of these can be found in /proc/net/arp, and the other in /proc/net/atm/arp. This patch adds a new function, neigh_table_init_no_netlink() which does everything the neigh_table_init() does, except add the table to the netlink all-arp-tables chain. In addition neigh_table_init() has a check that all tables on the chain have a distinct address family. The init call in clip.c is changed to call neigh_table_init_no_netlink(). Since ATM ARP tables are rather more complicated than can currently be handled by the available rtattrs in the netlink protocol, no functionality is lost by this patch, and non-ATM ARP manipulation via netlink is rescued. A more complete solution would involve a rtattr for ATM ARP entries and some way for the netlink code to give neigh_add and friends more information than just address family with which to find the correct ARP table. [ I've changed the assertion checking in neigh_table_init() to not use BUG_ON() while holding neigh_tbl_lock. Instead we remember that we found an existing tbl with the same family, and after dropping the lock we'll give a diagnostic kernel log message and a stack dump. -DaveM ] Signed-off-by: Simon Kelley <simon@thekelleys.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>		2006-05-12 14:56:08 -07:00
..
addr.c
addr.h
atm_misc.c
br2684.c
clip.c	[NEIGH]: Fix IP-over-ATM and ARP interaction.	2006-05-12 14:56:08 -07:00
common.c	[NET]: sem2mutex part 2	2006-03-20 22:35:41 -08:00
common.h
ioctl.c	[NET] sem2mutex: net/	2006-03-20 22:33:17 -08:00
ipcommon.c
ipcommon.h
Kconfig
lec_arpc.h
lec.c
lec.h
Makefile
mpc.c
mpc.h
mpoa_caches.c
mpoa_caches.h
mpoa_proc.c
pppoatm.c
proc.c
protocols.h
pvc.c
raw.c
resources.c	[NET]: sem2mutex part 2	2006-03-20 22:35:41 -08:00
resources.h	[NET]: sem2mutex part 2	2006-03-20 22:35:41 -08:00
signaling.c
signaling.h
svc.c