Commit 6cd8ec58 authored by Xin Long's avatar Xin Long Committed by Jakub Kicinski
Browse files

tipc: delete tipc_mtu_bad from tipc_udp_enable 



Since commit a4dfa72d ("tipc: set default MTU for UDP media"), it's
been no longer using dev->mtu for b->mtu, and the issue described in
commit 3de81b75 ("tipc: check minimum bearer MTU") doesn't exist
in UDP bearer any more.

Besides, dev->mtu can still be changed to a too small mtu after the UDP
bearer is created even with tipc_mtu_bad() check in tipc_udp_enable().
Note that NETDEV_CHANGEMTU event processing in tipc_l2_device_event()
doesn't really work for UDP bearer.

So this patch deletes the unnecessary tipc_mtu_bad from tipc_udp_enable.

Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Reviewed-by: default avatarTung Nguyen <tung.q.nguyen@dektech.com.au>
Link: https://lore.kernel.org/r/282f1f5cc40e6cad385aa1c60569e6c5b70e2fb3.1685371933.git.lucien.xin@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent c23515ad

net/tipc/bearer.c

+2 −2
Original line number Diff line number Diff line
@@ -431,7 +431,7 @@ int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b, 
	dev = dev_get_by_name(net, dev_name);

	if (!dev)

		return -ENODEV;

	if (tipc_mtu_bad(dev, 0)) {

	if (tipc_mtu_bad(dev)) {

		dev_put(dev);

		return -EINVAL;

	}
@@ -708,7 +708,7 @@ static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt, 
		test_and_set_bit_lock(0, &b->up);

		break;

	case NETDEV_CHANGEMTU:

		if (tipc_mtu_bad(dev, 0)) {

		if (tipc_mtu_bad(dev)) {

			bearer_disable(net, b);

			break;

		}

net/tipc/bearer.h

+2 −2
Original line number Diff line number Diff line
@@ -257,9 +257,9 @@ static inline void tipc_loopback_trace(struct net *net, 
}



/* check if device MTU is too low for tipc headers */

static inline bool tipc_mtu_bad(struct net_device *dev, unsigned int reserve)

static inline bool tipc_mtu_bad(struct net_device *dev)

{

	if (dev->mtu >= TIPC_MIN_BEARER_MTU + reserve)

	if (dev->mtu >= TIPC_MIN_BEARER_MTU)

		return false;

	netdev_warn(dev, "MTU too low for tipc bearer\n");

	return true;

net/tipc/udp_media.c

+0 −4
Original line number Diff line number Diff line
@@ -739,10 +739,6 @@ static int tipc_udp_enable(struct net *net, struct tipc_bearer *b, 
		udp_conf.use_udp_checksums = false;

		ub->ifindex = dev->ifindex;

		b->encap_hlen = sizeof(struct iphdr) + sizeof(struct udphdr);

		if (tipc_mtu_bad(dev, b->encap_hlen)) {

			err = -EINVAL;

			goto err;

		}

		b->mtu = b->media->mtu;

#if IS_ENABLED(CONFIG_IPV6)

	} else if (local.proto == htons(ETH_P_IPV6)) {