Re: Regression: net/ipv6/mld running system out of memory (not a leak)
From: Hangbin Liu <hidden>
Date: 2020-03-04 09:07:20
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
On Wed, Mar 04, 2020 at 08:44:29AM +0100, Rafał Miłecki wrote:
quoted
Hi Rafał, When review the code, I got confused. On the latest net code, we only add the allrouter address to multicast list in function 1) ipv6_add_dev(), which only called when there is no idev. But link down and up would not re-create idev. 2) dev_forward_change(), which only be called during forward change, this function will handle add/remove allrouter address correctly.Sharp eye! You're right, I tracked (with just a pr_info) all usages of in6addr_linklocal_allrouters and none gets triggered during my testing routine. I'm wondering if I should start blaming my OpenWrt user space now.
Yeah...Hope you could help dig more.
quoted
So I still don't know how you could added the ff02::2 on same dev multi times. Does just do `ip link set $dev down; ip link set $dev up` reproduce your problem? Or did I miss something?A bit old-fashioned with ifconfig but basically yes, that's my test: iw phy phy0 interface add mon-phy0 type monitor
What does this step do? Is there a corresponding command for ip link?
for i in $(seq 1 10); do ifconfig mon-phy0 up; ifconfig mon-phy0 down; done iw dev mon-phy0 del
The other cmd looks normal. BTW, I have create a new patch. The previous one
will leak ff01::1, ff02::1, ff01::2 as the link up will not re-add them.
The new patch will join and leave all node/route address when link up/down
instead of store them. But I don't think it could resolve your issue as the
code logic is not changed. If you like, you can have a try.
Thanks
Hangbin
From 9cf504dc30198133e470ea783c3fa53a8f56a20a Mon Sep 17 00:00:00 2001
From: Hangbin Liu <redacted>
Date: Tue, 3 Mar 2020 20:58:39 +0800
Subject: [PATCH] ipv6/mcast: join and leave allnodes, allrouters addresses
when link up/down
This patch fixes two issues:
1) When link up with IPv6 forwarding enabled, we forgot to join
sitelocal_allrouters(ff01::2) and interfacelocal_allrouters(ff05::2),
like what we do in function dev_forward_change()
2) When link down, there is no listener for the allnodes, allrouters
addresses. So we should remove them instead of storing the info in
idev->mc_tomb.
To fix these two issue, I add two new functions ipv6_mc_join_localaddr()
and ipv6_mc_leave_localaddr() to handle these addresses. And just join
leave the group in ipv6_mc_{up, down}.
Signed-off-by: Hangbin Liu <redacted>
---
net/ipv6/addrconf.c | 22 +++++++---------------
net/ipv6/mcast.c | 45 ++++++++++++++++++++++++++++++++++-----------
2 files changed, 41 insertions(+), 26 deletions(-)
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 164c71c54b5c..8e39f569beaa 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c@@ -449,16 +449,6 @@ static struct inet6_dev *ipv6_add_dev(struct net_device *dev) /* protected by rtnl_lock */ rcu_assign_pointer(dev->ip6_ptr, ndev); - /* Join interface-local all-node multicast group */ - ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes); - - /* Join all-node multicast group */ - ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes); - - /* Join all-router multicast group if forwarding is set */ - if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST)) - ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters); - return ndev; err_release:
@@ -481,7 +471,7 @@ static struct inet6_dev *ipv6_find_idev(struct net_device *dev) return idev; } - if (dev->flags&IFF_UP) + if (dev->flags & IFF_UP && dev->flags & IFF_MULTICAST) ipv6_mc_up(idev); return idev; }
@@ -795,7 +785,7 @@ static void dev_forward_change(struct inet6_dev *idev) dev = idev->dev; if (idev->cnf.forwarding) dev_disable_lro(dev); - if (dev->flags & IFF_MULTICAST) { + if (dev->flags & IFF_UP && dev->flags & IFF_MULTICAST) { if (idev->cnf.forwarding) { ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters); ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
@@ -3554,7 +3544,8 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event, } if (!IS_ERR_OR_NULL(idev)) { - if (idev->if_flags & IF_READY) { + if (idev->if_flags & IF_READY && + dev->flags & IFF_MULTICAST) { /* device is already configured - * but resend MLD reports, we might * have roamed and need to update
@@ -3839,8 +3830,9 @@ static int addrconf_ifdown(struct net_device *dev, int how) /* Step 5: Discard anycast and multicast list */ if (how) { ipv6_ac_destroy_dev(idev); - ipv6_mc_destroy_dev(idev); - } else { + if (dev->flags & IFF_MULTICAST) + ipv6_mc_destroy_dev(idev); + } else if (dev->flags & IFF_MULTICAST){ ipv6_mc_down(idev); }
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index eaa4c2cc2fbb..1512ca906b36 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c@@ -2529,11 +2529,44 @@ void ipv6_mc_remap(struct inet6_dev *idev) /* Device going down */ +static void ipv6_mc_join_localaddr(struct inet6_dev *idev) +{ + struct net_device *dev; + + dev = idev->dev; + + /* Join interface-local all-node multicast group */ + ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes); + + /* Join all-node multicast group */ + ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes); + + /* Join all-router multicast group if forwarding is set */ + if (idev->cnf.forwarding) { + ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters); + ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters); + ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters); + } +} + +static void ipv6_mc_leave_localaddr(struct inet6_dev *idev) +{ + __ipv6_dev_mc_dec(idev, &in6addr_interfacelocal_allnodes); + __ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes); + + if (idev->cnf.forwarding) { + __ipv6_dev_mc_dec(idev, &in6addr_interfacelocal_allrouters); + __ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters); + __ipv6_dev_mc_dec(idev, &in6addr_sitelocal_allrouters); + } +} + void ipv6_mc_down(struct inet6_dev *idev) { struct ifmcaddr6 *i; /* Withdraw multicast list */ + ipv6_mc_leave_localaddr(idev); read_lock_bh(&idev->lock);
@@ -2564,7 +2597,7 @@ void ipv6_mc_up(struct inet6_dev *idev) { struct ifmcaddr6 *i; - /* Install multicast list, except for all-nodes (already installed) */ + ipv6_mc_join_localaddr(idev); read_lock_bh(&idev->lock); ipv6_mc_reset(idev);
@@ -2603,16 +2636,6 @@ void ipv6_mc_destroy_dev(struct inet6_dev *idev) ipv6_mc_down(idev); mld_clear_delrec(idev); - /* Delete all-nodes address. */ - /* We cannot call ipv6_dev_mc_dec() directly, our caller in - * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will - * fail. - */ - __ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes); - - if (idev->cnf.forwarding) - __ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters); - write_lock_bh(&idev->lock); while ((i = idev->mc_list) != NULL) { idev->mc_list = i->next;
--
2.19.2