This is a note to let you know that I've just added the patch titled
net: avoid reference counter overflows on fib_rules in multicast forwarding
to the 3.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-avoid-reference-counter-overflows-on-fib_rules-in-multicast-forwarding.patch
and it can be found in the queue-3.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Feb 4 08:37:18 PST 2014
From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Date: Mon, 13 Jan 2014 02:45:22 +0100
Subject: net: avoid reference counter overflows on fib_rules in multicast forwarding
From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
[ Upstream commit 95f4a45de1a0f172b35451fc52283290adb21f6e ]
Bob Falken reported that after 4G packets, multicast forwarding stopped
working. This was because of a rule reference counter overflow which
freed the rule as soon as the overflow happend.
This patch solves this by adding the FIB_LOOKUP_NOREF flag to
fib_rules_lookup calls. This is safe even from non-rcu locked sections
as in this case the flag only implies not taking a reference to the rule,
which we don't need at all.
Rules only hold references to the namespace, which are guaranteed to be
available during the call of the non-rcu protected function reg_vif_xmit
because of the interface reference which itself holds a reference to
the net namespace.
Fixes: f0ad0860d01e47 ("ipv4: ipmr: support multiple tables")
Fixes: d1db275dd3f6e4 ("ipv6: ip6mr: support multiple tables")
Reported-by: Bob Falken <NetFestivalHaveFun@xxxxxxx>
Cc: Patrick McHardy <kaber@xxxxxxxxx>
Cc: Thomas Graf <tgraf@xxxxxxx>
Cc: Julian Anastasov <ja@xxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Signed-off-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/ipmr.c | 7 +++++--
net/ipv6/ip6mr.c | 7 +++++--
2 files changed, 10 insertions(+), 4 deletions(-)
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -154,9 +154,12 @@ static struct mr_table *ipmr_get_table(s
static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
struct mr_table **mrt)
{
- struct ipmr_result res;
- struct fib_lookup_arg arg = { .result = &res, };
int err;
+ struct ipmr_result res;
+ struct fib_lookup_arg arg = {
+ .result = &res,
+ .flags = FIB_LOOKUP_NOREF,
+ };
err = fib_rules_lookup(net->ipv4.mr_rules_ops,
flowi4_to_flowi(flp4), 0, &arg);
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -138,9 +138,12 @@ static struct mr6_table *ip6mr_get_table
static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
struct mr6_table **mrt)
{
- struct ip6mr_result res;
- struct fib_lookup_arg arg = { .result = &res, };
int err;
+ struct ip6mr_result res;
+ struct fib_lookup_arg arg = {
+ .result = &res,
+ .flags = FIB_LOOKUP_NOREF,
+ };
err = fib_rules_lookup(net->ipv6.mr6_rules_ops,
flowi6_to_flowi(flp6), 0, &arg);
Patches currently in stable-queue which might be from hannes@xxxxxxxxxxxxxxxxxxx are
queue-3.4/net-avoid-reference-counter-overflows-on-fib_rules-in-multicast-forwarding.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html