From 82f17091e68254d1612b42cf23291cad63cfaf04 Mon Sep 17 00:00:00 2001 From: Francesco Ruggeri Date: Mon, 9 Mar 2015 11:51:04 -0700 Subject: net: delete stale packet_mclist entries When an interface is deleted from a net namespace the ifindex in the corresponding entries in PF_PACKET sockets' mclists becomes stale. This can create inconsistencies if later an interface with the same ifindex is moved from a different namespace (not that unlikely since ifindexes are per-namespace). In particular we saw problems with dev->promiscuity, resulting in "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken" warnings and EOVERFLOW failures of setsockopt(PACKET_ADD_MEMBERSHIP). This patch deletes the mclist entries for interfaces that are deleted. Since this now causes setsockopt(PACKET_DROP_MEMBERSHIP) to fail with EADDRNOTAVAIL if called after the interface is deleted, also make packet_mc_drop not fail. Signed-off-by: Francesco Ruggeri Signed-off-by: David S. Miller --- net/packet/af_packet.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) (limited to 'net/packet') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 5bf1e968a728..f8db7064d81c 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3123,11 +3123,18 @@ static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, return 0; } -static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what) +static void packet_dev_mclist_delete(struct net_device *dev, + struct packet_mclist **mlp) { - for ( ; i; i = i->next) { - if (i->ifindex == dev->ifindex) - packet_dev_mc(dev, i, what); + struct packet_mclist *ml; + + while ((ml = *mlp) != NULL) { + if (ml->ifindex == dev->ifindex) { + packet_dev_mc(dev, ml, -1); + *mlp = ml->next; + kfree(ml); + } else + mlp = &ml->next; } } @@ -3204,12 +3211,11 @@ static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) packet_dev_mc(dev, ml, -1); kfree(ml); } - rtnl_unlock(); - return 0; + break; } } rtnl_unlock(); - return -EADDRNOTAVAIL; + return 0; } static void packet_flush_mclist(struct sock *sk) @@ -3559,7 +3565,7 @@ static int packet_notifier(struct notifier_block *this, switch (msg) { case NETDEV_UNREGISTER: if (po->mclist) - packet_dev_mclist(dev, po->mclist, -1); + packet_dev_mclist_delete(dev, &po->mclist); /* fallthrough */ case NETDEV_DOWN: -- cgit v1.2.3-59-g8ed1b