linux-stable.git/net/bridge, branch linux-4.0.y

bridge: fix br_stp_set_bridge_priority race conditions

2015-07-10T16:45:33+00:00

[ Upstream commit 2dab80a8b486f02222a69daca6859519e05781d9 ]

After the ->set() spinlocks were removed br_stp_set_bridge_priority
was left running without any protection when used via sysfs. It can
race with port add/del and could result in use-after-free cases and
corrupted lists. Tested by running port add/del in a loop with stp
enabled while setting priority in a loop, crashes are easily
reproducible.
The spinlocks around sysfs ->set() were removed in commit:
14f98f258f19 ("bridge: range check STP parameters")
There's also a race condition in the netlink priority support that is
fixed by this change, but it was introduced recently and the fixes tag
covers it, just in case it's needed the commit is:
af615762e972 ("bridge: add ageing_time, stp_state, priority over netlink")

Signed-off-by: Nikolay Aleksandrov 
Fixes: 14f98f258f19 ("bridge: range check STP parameters")
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: fix multicast router rlist endless loop

2015-07-10T16:45:33+00:00

[ Upstream commit 1a040eaca1a22f8da8285ceda6b5e4a2cb704867 ]

Since the addition of sysfs multicast router support if one set
multicast_router to "2" more than once, then the port would be added to
the hlist every time and could end up linking to itself and thus causing an
endless loop for rlist walkers.
So to reproduce just do:
echo 2 > multicast_router; echo 2 > multicast_router;
in a bridge port and let some igmp traffic flow, for me it hangs up
in br_multicast_flood().
Fix this by adding a check in br_multicast_add_router() if the port is
already linked.
The reason this didn't happen before the addition of multicast_router
sysfs entries is because there's a !hlist_unhashed check that prevents
it.

Signed-off-by: Nikolay Aleksandrov 
Fixes: 0909e11758bd ("bridge: Add multicast_router sysfs entries")
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: disable softirqs around br_fdb_update to avoid lockup

2015-06-23T00:03:24+00:00

[ Upstream commit c4c832f89dc468cf11dc0dd17206bace44526651 ]

br_fdb_update() can be called in process context in the following way:
br_fdb_add() -> __br_fdb_add() -> br_fdb_update() (if NTF_USE flag is set)
so we need to disable softirqs because there are softirq users of the
hash_lock. One easy way to reproduce this is to modify the bridge utility
to set NTF_USE, enable stp and then set maxageing to a low value so
br_fdb_cleanup() is called frequently and then just add new entries in
a loop. This happens because br_fdb_cleanup() is called from timer/softirq
context. The spin locks in br_fdb_update were _bh before commit f8ae737deea1
("[BRIDGE]: forwarding remove unneeded preempt and bh diasables")
and at the time that commit was correct because br_fdb_update() couldn't be
called from process context, but that changed after commit:
292d1398983f ("bridge: add NTF_USE support")
Using local_bh_disable/enable around br_fdb_update() allows us to keep
using the spin_lock/unlock in br_fdb_update for the fast-path.

Signed-off-by: Nikolay Aleksandrov 
Fixes: 292d1398983f ("bridge: add NTF_USE support")
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: fix br_multicast_query_expired() bug

2015-06-23T00:03:23+00:00

[ Upstream commit 71d9f6149cac8fc6646adfb2a6f3b0de6ddd23f6 ]

br_multicast_query_expired() querier argument is a pointer to
a struct bridge_mcast_querier :

struct bridge_mcast_querier {
        struct br_ip addr;
        struct net_bridge_port __rcu    *port;
};

Intent of the code was to clear port field, not the pointer to querier.

Fixes: 2cd4143192e8 ("bridge: memorize and export selected IGMP/MLD querier port")
Signed-off-by: Eric Dumazet 
Acked-by: Thadeu Lima de Souza Cascardo 
Acked-by: Linus Lüssing 
Cc: Linus Lüssing 
Cc: Steinar H. Gunderson 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: fix parsing of MLDv2 reports

2015-06-23T00:03:21+00:00

[ Upstream commit 47cc84ce0c2fe75c99ea5963c4b5704dd78ead54 ]

When more than a multicast address is present in a MLDv2 report, all but
the first address is ignored, because the code breaks out of the loop if
there has not been an error adding that address.

This has caused failures when two guests connected through the bridge
tried to communicate using IPv6. Neighbor discoveries would not be
transmitted to the other guest when both used a link-local address and a
static address.

This only happens when there is a MLDv2 querier in the network.

The fix will only break out of the loop when there is a failure adding a
multicast address.

The mdb before the patch:

dev ovirtmgmt port vnet0 grp ff02::1:ff7d:6603 temp
dev ovirtmgmt port vnet1 grp ff02::1:ff7d:6604 temp
dev ovirtmgmt port bond0.86 grp ff02::2 temp

After the patch:

dev ovirtmgmt port vnet0 grp ff02::1:ff7d:6603 temp
dev ovirtmgmt port vnet1 grp ff02::1:ff7d:6604 temp
dev ovirtmgmt port bond0.86 grp ff02::fb temp
dev ovirtmgmt port bond0.86 grp ff02::2 temp
dev ovirtmgmt port bond0.86 grp ff02::d temp
dev ovirtmgmt port vnet0 grp ff02::1:ff00:76 temp
dev ovirtmgmt port bond0.86 grp ff02::16 temp
dev ovirtmgmt port vnet1 grp ff02::1:ff00:77 temp
dev ovirtmgmt port bond0.86 grp ff02::1:ff00:def temp
dev ovirtmgmt port bond0.86 grp ff02::1:ffa1:40bf temp

Fixes: 08b202b67264 ("bridge br_multicast: IPv6 MLD support.")
Reported-by: Rik Theys 
Signed-off-by: Thadeu Lima de Souza Cascardo 
Tested-by: Rik Theys 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netfilter: bridge: really save frag_max_size between PRE and POST_ROUTING

2015-05-06T20:04:08+00:00

commit 0b67c43ce36a9964f1d5e3f973ee19eefd3f9f8f upstream.

We also need to save/store in forward, else br_parse_ip_options call
will zero frag_max_size as well.

Fixes: 93fdd47e5 ('bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING')
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

bridge: reset bridge mtu after deleting an interface

2015-03-14T23:12:38+00:00

On adding an interface br_add_if() sets the MTU to the min of
all the interfaces. Do the same thing on removing an interface too
in br_del_if.

Signed-off-by: Venkat Venkatsubra 
Acked-by: Roopa Prabhu 
Signed-off-by: David S. Miller

net: bridge: add compile-time assert for cb struct size

2015-03-03T19:07:04+00:00

make build fail if structure no longer fits into ->cb storage.

Signed-off-by: Florian Westphal 
Signed-off-by: David S. Miller

bridge: netfilter: Move sysctl-specific error code inside #ifdef

2015-02-12T16:44:46+00:00

If CONFIG_SYSCTL=n:

    net/bridge/br_netfilter.c: In function ‘br_netfilter_init’:
    net/bridge/br_netfilter.c:996: warning: label ‘err1’ defined but not used

Move the label and the code after it inside the existing #ifdef to get
rid of the warning.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-02-09T22:35:57+00:00

Signed-off-by: David S. Miller