From 0e615e9601a15efeeb8942cf7cd4dadba0c8c5a7 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Fri, 20 Nov 2015 13:54:19 +0100 Subject: net: ipmr: fix static mfc/dev leaks on table destruction When destroying an mrt table the static mfc entries and the static devices are kept, which leads to devices that can never be destroyed (because of refcnt taken) and leaked memory, for example: unreferenced object 0xffff880034c144c0 (size 192): comm "mfc-broken", pid 4777, jiffies 4320349055 (age 46001.964s) hex dump (first 32 bytes): 98 53 f0 34 00 88 ff ff 98 53 f0 34 00 88 ff ff .S.4.....S.4.... ef 0a 0a 14 01 02 03 04 00 00 00 00 01 00 00 00 ................ backtrace: [] kmemleak_alloc+0x4e/0xb0 [] kmem_cache_alloc+0x190/0x300 [] ip_mroute_setsockopt+0x5cb/0x910 [] do_ip_setsockopt.isra.11+0x105/0xff0 [] ip_setsockopt+0x30/0xa0 [] raw_setsockopt+0x33/0x90 [] sock_common_setsockopt+0x14/0x20 [] SyS_setsockopt+0x71/0xc0 [] entry_SYSCALL_64_fastpath+0x16/0x7a [] 0xffffffffffffffff Make sure that everything is cleaned on netns destruction. Signed-off-by: Nikolay Aleksandrov Reviewed-by: Cong Wang Signed-off-by: David S. Miller --- net/ipv4/ipmr.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'net/ipv4/ipmr.c') diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 92dd4b74d513..292123bc30fa 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -134,7 +134,7 @@ static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm); static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc, int cmd); -static void mroute_clean_tables(struct mr_table *mrt); +static void mroute_clean_tables(struct mr_table *mrt, bool all); static void ipmr_expire_process(unsigned long arg); #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES @@ -350,7 +350,7 @@ static struct mr_table *ipmr_new_table(struct net *net, u32 id) static void ipmr_free_table(struct mr_table *mrt) { del_timer_sync(&mrt->ipmr_expire_timer); - mroute_clean_tables(mrt); + mroute_clean_tables(mrt, true); kfree(mrt); } @@ -1208,7 +1208,7 @@ static int ipmr_mfc_add(struct net *net, struct mr_table *mrt, * Close the multicast socket, and clear the vif tables etc */ -static void mroute_clean_tables(struct mr_table *mrt) +static void mroute_clean_tables(struct mr_table *mrt, bool all) { int i; LIST_HEAD(list); @@ -1217,8 +1217,9 @@ static void mroute_clean_tables(struct mr_table *mrt) /* Shut down all active vif entries */ for (i = 0; i < mrt->maxvif; i++) { - if (!(mrt->vif_table[i].flags & VIFF_STATIC)) - vif_delete(mrt, i, 0, &list); + if (!all && (mrt->vif_table[i].flags & VIFF_STATIC)) + continue; + vif_delete(mrt, i, 0, &list); } unregister_netdevice_many(&list); @@ -1226,7 +1227,7 @@ static void mroute_clean_tables(struct mr_table *mrt) for (i = 0; i < MFC_LINES; i++) { list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[i], list) { - if (c->mfc_flags & MFC_STATIC) + if (!all && (c->mfc_flags & MFC_STATIC)) continue; list_del_rcu(&c->list); mroute_netlink_event(mrt, c, RTM_DELROUTE); @@ -1261,7 +1262,7 @@ static void mrtsock_destruct(struct sock *sk) NETCONFA_IFINDEX_ALL, net->ipv4.devconf_all); RCU_INIT_POINTER(mrt->mroute_sk, NULL); - mroute_clean_tables(mrt); + mroute_clean_tables(mrt, false); } } rtnl_unlock(); -- cgit v1.2.3 From fbdd29bfd2da979b7ac6a0084af56624156c1069 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Tue, 24 Nov 2015 17:09:30 +0100 Subject: net: ipmr, ip6mr: fix vif/tunnel failure race condition Since (at least) commit b17a7c179dd3 ("[NET]: Do sysfs registration as part of register_netdevice."), netdev_run_todo() deals only with unregistration, so we don't need to do the rtnl_unlock/lock cycle to finish registration when failing pimreg or dvmrp device creation. In fact that opens a race condition where someone can delete the device while rtnl is unlocked because it's fully registered. The problem gets worse when netlink support is introduced as there are more points of entry that can cause it and it also makes reusing that code correctly impossible. Signed-off-by: Nikolay Aleksandrov Reviewed-by: Cong Wang Signed-off-by: David S. Miller --- net/ipv4/ipmr.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'net/ipv4/ipmr.c') diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 292123bc30fa..c3a38353f5dc 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -441,10 +441,6 @@ struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v) return dev; failure: - /* allow the register to be completed before unregistering. */ - rtnl_unlock(); - rtnl_lock(); - unregister_netdevice(dev); return NULL; } @@ -540,10 +536,6 @@ static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt) return dev; failure: - /* allow the register to be completed before unregistering. */ - rtnl_unlock(); - rtnl_lock(); - unregister_netdevice(dev); return NULL; } -- cgit v1.2.3