From 8d59c3a6376bbc6dd3f7303968a719ffba75a4f1 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Tue, 9 Oct 2018 17:48:14 +0200 Subject: net: ipv4: update fnhe_pmtu when first hop's MTU changes [ Upstream commit af7d6cce53694a88d6a1bb60c9a239a6a5144459 ] Since commit 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions"), exceptions get deprecated separately from cached routes. In particular, administrative changes don't clear PMTU anymore. As Stefano described in commit e9fa1495d738 ("ipv6: Reflect MTU changes on PMTU of exceptions for MTU-less routes"), the PMTU discovered before the local MTU change can become stale: - if the local MTU is now lower than the PMTU, that PMTU is now incorrect - if the local MTU was the lowest value in the path, and is increased, we might discover a higher PMTU Similarly to what commit e9fa1495d738 did for IPv6, update PMTU in those cases. If the exception was locked, the discovered PMTU was smaller than the minimal accepted PMTU. In that case, if the new local MTU is smaller than the current PMTU, let PMTU discovery figure out if locking of the exception is still needed. To do this, we need to know the old link MTU in the NETDEV_CHANGEMTU notifier. By the time the notifier is called, dev->mtu has been changed. This patch adds the old MTU as additional information in the notifier structure, and a new call_netdevice_notifiers_u32() function. Fixes: 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions") Signed-off-by: Sabrina Dubroca Reviewed-by: Stefano Brivio Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/dev.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index b85e789044d5..15e3bb94156b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1664,6 +1664,28 @@ int call_netdevice_notifiers(unsigned long val, struct net_device *dev) } EXPORT_SYMBOL(call_netdevice_notifiers); +/** + * call_netdevice_notifiers_mtu - call all network notifier blocks + * @val: value passed unmodified to notifier function + * @dev: net_device pointer passed unmodified to notifier function + * @arg: additional u32 argument passed to the notifier function + * + * Call all network notifier blocks. Parameters and return value + * are as for raw_notifier_call_chain(). + */ +static int call_netdevice_notifiers_mtu(unsigned long val, + struct net_device *dev, u32 arg) +{ + struct netdev_notifier_info_ext info = { + .info.dev = dev, + .ext.mtu = arg, + }; + + BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); + + return call_netdevice_notifiers_info(val, dev, &info.info); +} + #ifdef CONFIG_NET_INGRESS static struct static_key ingress_needed __read_mostly; @@ -6589,14 +6611,16 @@ int dev_set_mtu(struct net_device *dev, int new_mtu) err = __dev_set_mtu(dev, new_mtu); if (!err) { - err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); + err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, + orig_mtu); err = notifier_to_errno(err); if (err) { /* setting mtu back and notifying everyone again, * so that they have a chance to revert changes. */ __dev_set_mtu(dev, orig_mtu); - call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); + call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, + new_mtu); } } return err; -- cgit v1.2.3 From 4a80b1feaee77c9108765cf696c1bc2196393126 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 17 Nov 2018 21:57:02 -0800 Subject: net-gro: reset skb->pkt_type in napi_reuse_skb() [ Upstream commit 33d9a2c72f086cbf1087b2fd2d1a15aa9df14a7f ] eth_type_trans() assumes initial value for skb->pkt_type is PACKET_HOST. This is indeed the value right after a fresh skb allocation. However, it is possible that GRO merged a packet with a different value (like PACKET_OTHERHOST in case macvlan is used), so we need to make sure napi->skb will have pkt_type set back to PACKET_HOST. Otherwise, valid packets might be dropped by the stack because their pkt_type is not PACKET_HOST. napi_reuse_skb() was added in commit 96e93eab2033 ("gro: Add internal interfaces for VLAN"), but this bug always has been there. Fixes: 96e93eab2033 ("gro: Add internal interfaces for VLAN") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/dev.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index 15e3bb94156b..071c589f7994 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4756,6 +4756,10 @@ static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) skb->vlan_tci = 0; skb->dev = napi->dev; skb->skb_iif = 0; + + /* eth_type_trans() assumes pkt_type is PACKET_HOST */ + skb->pkt_type = PACKET_HOST; + skb->encapsulation = 0; skb_shinfo(skb)->gso_type = 0; skb->truesize = SKB_TRUESIZE(skb_end_offset(skb)); -- cgit v1.2.3