BMC/Intel-BMC/linux.git/net/bridge/br_mdb.c, branch dev

bridge: mdb: fix delmdb state in the notification

2015-07-29T22:02:30+00:00

Since mdb states were introduced when deleting an entry the state was left as it was set in the delete request from the user which leads to the following output when doing a monitor (for example): $ bridge mdb add dev br0 port eth3 grp 239.0.0.1 permanent (monitor) dev br0 port eth3 grp 239.0.0.1 permanent $ bridge mdb del dev br0 port eth3 grp 239.0.0.1 permanent (monitor) dev br0 port eth3 grp 239.0.0.1 temp ^^^ Note the "temp" state in the delete notification which is wrong since the entry was permanent, the state in a delete is always reported as "temp" regardless of the real state of the entry. After this patch: $ bridge mdb add dev br0 port eth3 grp 239.0.0.1 permanent (monitor) dev br0 port eth3 grp 239.0.0.1 permanent $ bridge mdb del dev br0 port eth3 grp 239.0.0.1 permanent (monitor) dev br0 port eth3 grp 239.0.0.1 permanent There's one important note to make here that the state is actually not matched when doing a delete, so one can delete a permanent entry by stating "temp" in the end of the command, I've chosen this fix in order not to break user-space tools which rely on this (incorrect) behaviour. So to give an example after this patch and using the wrong state: $ bridge mdb add dev br0 port eth3 grp 239.0.0.1 permanent (monitor) dev br0 port eth3 grp 239.0.0.1 permanent $ bridge mdb del dev br0 port eth3 grp 239.0.0.1 temp (monitor) dev br0 port eth3 grp 239.0.0.1 permanent Note the state of the entry that got deleted is correct in the notification. Signed-off-by: Nikolay Aleksandrov Fixes: ccb1c31a7a87 ("bridge: add flags to distinguish permanent mdb entires") Signed-off-by: David S. Miller

bridge: mdb: fix double add notification

2015-07-16T00:15:01+00:00

Since the mdb add/del code was introduced there have been 2 br_mdb_notify calls when doing br_mdb_add() resulting in 2 notifications on each add. Example: Command: bridge mdb add dev br0 port eth1 grp 239.0.0.1 permanent Before patch: root@debian:~# bridge monitor all [MDB]dev br0 port eth1 grp 239.0.0.1 permanent [MDB]dev br0 port eth1 grp 239.0.0.1 permanent After patch: root@debian:~# bridge monitor all [MDB]dev br0 port eth1 grp 239.0.0.1 permanent Signed-off-by: Nikolay Aleksandrov Fixes: cfd567543590 ("bridge: add support of adding and deleting mdb entries") Signed-off-by: David S. Miller

bridge: mdb: allow the user to delete mdb entry if there's a querier

2015-07-11T01:18:00+00:00

Until now when a querier was present static entries couldn't be deleted. Fix this and allow the user to manipulate the mdb with or without a querier. Signed-off-by: Satish Ashok Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller

bridge: mdb: zero out the local br_ip variable before use

2015-07-08T23:10:40+00:00

Since commit b0e9a30dd669 ("bridge: Add vlan id to multicast groups") there's a check in br_ip_equal() for a matching vlan id, but the mdb functions were not modified to use (or at least zero it) so when an entry was added it would have a garbage vlan id (from the local br_ip variable in __br_mdb_add/del) and this would prevent it from being matched and also deleted. So zero out the whole local ip var to protect ourselves from future changes and also to fix the current bug, since there's no vlan id support in the mdb uapi - use always vlan id 0. Example before patch: root@debian:~# bridge mdb add dev br0 port eth1 grp 239.0.0.1 permanent root@debian:~# bridge mdb dev br0 port eth1 grp 239.0.0.1 permanent root@debian:~# bridge mdb del dev br0 port eth1 grp 239.0.0.1 permanent RTNETLINK answers: Invalid argument After patch: root@debian:~# bridge mdb add dev br0 port eth1 grp 239.0.0.1 permanent root@debian:~# bridge mdb dev br0 port eth1 grp 239.0.0.1 permanent root@debian:~# bridge mdb del dev br0 port eth1 grp 239.0.0.1 permanent root@debian:~# bridge mdb Signed-off-by: Nikolay Aleksandrov Fixes: b0e9a30dd669 ("bridge: Add vlan id to multicast groups") Signed-off-by: David S. Miller

bridge: mdb: start delete timer for temp static entries

2015-07-08T21:52:58+00:00

Start the delete timer when adding temp static entries so they can expire. Signed-off-by: Satish Ashok Signed-off-by: Nikolay Aleksandrov Fixes: ccb1c31a7a87 ("bridge: add flags to distinguish permanent mdb entires") Signed-off-by: David S. Miller

bridge/mdb: remove wrong use of NLM_F_MULTI

2015-04-29T18:59:16+00:00

NLM_F_MULTI must be used only when a NLMSG_DONE message is sent. In fact, it is sent only at the end of a dump. Libraries like libnl will wait forever for NLMSG_DONE. Fixes: 37a393bc4932 ("bridge: notify mdb changes via netlink") CC: Cong Wang CC: Stephen Hemminger CC: bridge@lists.linux-foundation.org Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

netlink: make nlmsg_end() and genlmsg_end() void

2015-01-18T06:03:45+00:00

Contrary to common expectations for an "int" return, these functions return only a positive value -- if used correctly they cannot even return 0 because the message header will necessarily be in the skb. This makes the very common pattern of if (genlmsg_end(...) < 0) { ... } be a whole bunch of dead code. Many places also simply do return nlmsg_end(...); and the caller is expected to deal with it. This also commonly (at least for me) causes errors, because it is very common to write if (my_function(...)) /* error condition */ and if my_function() does "return nlmsg_end()" this is of course wrong. Additionally, there's not a single place in the kernel that actually needs the message length returned, and if anyone needs it later then it'll be very easy to just use skb->len there. Remove this, and make the functions void. This removes a bunch of dead code as described above. The patch adds lines because I did - return nlmsg_end(...); + nlmsg_end(...); + return 0; I could have preserved all the function's return values by returning skb->len, but instead I've audited all the places calling the affected functions and found that none cared. A few places actually compared the return value with <= 0 in dump functionality, but that could just be changed to < 0 with no change in behaviour, so I opted for the more efficient version. One instance of the error I've made numerous times now is also present in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't check for <0 or <=0 and thus broke out of the loop every single time. I've preserved this since it will (I think) have caused the messages to userspace to be formatted differently with just a single message for every SKB returned to userspace. It's possible that this isn't needed for the tools that actually use this, but I don't even know what they are so couldn't test that changing this behaviour would be acceptable. Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

bridge: use MDBA_SET_ENTRY_MAX for maxtype in nlmsg_parse()

2015-01-16T00:37:20+00:00

This is just a cleanup, because in the current code MDBA_SET_ENTRY_MAX == MDBA_SET_ENTRY. Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

bridge: rename struct bridge_mcast_query/querier

2014-06-11T06:50:46+00:00

The current naming of these two structs is very random, in that reversing their naming would not make any semantical difference. This patch tries to make the naming less confusing by giving them a more specific, distinguishable naming. This is also useful for the upcoming patches reintroducing the "struct bridge_mcast_querier" but for storing information about the selected querier (no matter if our own or a foreign querier). Signed-off-by: Linus Lüssing Signed-off-by: David S. Miller

Revert "bridge: only expire the mdb entry when query is received"

2013-10-22T18:41:02+00:00

While this commit was a good attempt to fix issues occuring when no multicast querier is present, this commit still has two more issues: 1) There are cases where mdb entries do not expire even if there is a querier present. The bridge will unnecessarily continue flooding multicast packets on the according ports. 2) Never removing an mdb entry could be exploited for a Denial of Service by an attacker on the local link, slowly, but steadily eating up all memory. Actually, this commit became obsolete with "bridge: disable snooping if there is no querier" (b00589af3b) which included fixes for a few more cases. Therefore reverting the following commits (the commit stated in the commit message plus three of its follow up fixes): ==================== Revert "bridge: update mdb expiration timer upon reports." This reverts commit f144febd93d5ee534fdf23505ab091b2b9088edc. Revert "bridge: do not call setup_timer() multiple times" This reverts commit 1faabf2aab1fdaa1ace4e8c829d1b9cf7bfec2f1. Revert "bridge: fix some kernel warning in multicast timer" This reverts commit c7e8e8a8f7a70b343ca1e0f90a31e35ab2d16de1. Revert "bridge: only expire the mdb entry when query is received" This reverts commit 9f00b2e7cf241fa389733d41b615efdaa2cb0f5b. ==================== CC: Cong Wang Signed-off-by: Linus Lüssing Reviewed-by: Vlad Yasevich Signed-off-by: David S. Miller