linux-stable.git/net, branch v4.3.3

net_sched: fix qdisc_tree_decrease_qlen() races

2015-12-15T05:41:04+00:00

[ Upstream commit 4eaf3b84f2881c9c028f1d5e76c52ab575fe3a66 ]

qdisc_tree_decrease_qlen() suffers from two problems on multiqueue
devices.

One problem is that it updates sch->q.qlen and sch->qstats.drops
on the mq/mqprio root qdisc, while it should not : Daniele
reported underflows errors :
[  681.774821] PAX: sch->q.qlen: 0 n: 1
[  681.774825] PAX: size overflow detected in function qdisc_tree_decrease_qlen net/sched/sch_api.c:769 cicus.693_49 min, count: 72, decl: qlen; num: 0; context: sk_buff_head;
[  681.774954] CPU: 2 PID: 19 Comm: ksoftirqd/2 Tainted: G           O    4.2.6.201511282239-1-grsec #1
[  681.774955] Hardware name: ASUSTeK COMPUTER INC. X302LJ/X302LJ, BIOS X302LJ.202 03/05/2015
[  681.774956]  ffffffffa9a04863 0000000000000000 0000000000000000 ffffffffa990ff7c
[  681.774959]  ffffc90000d3bc38 ffffffffa95d2810 0000000000000007 ffffffffa991002b
[  681.774960]  ffffc90000d3bc68 ffffffffa91a44f4 0000000000000001 0000000000000001
[  681.774962] Call Trace:
[  681.774967]  [] dump_stack+0x4c/0x7f
[  681.774970]  [] report_size_overflow+0x34/0x50
[  681.774972]  [] qdisc_tree_decrease_qlen+0x152/0x160
[  681.774976]  [] fq_codel_dequeue+0x7b1/0x820 [sch_fq_codel]
[  681.774978]  [] ? qdisc_peek_dequeued+0xa0/0xa0 [sch_fq_codel]
[  681.774980]  [] __qdisc_run+0x4d/0x1d0
[  681.774983]  [] net_tx_action+0xc2/0x160
[  681.774985]  [] __do_softirq+0xf1/0x200
[  681.774987]  [] run_ksoftirqd+0x1e/0x30
[  681.774989]  [] smpboot_thread_fn+0x150/0x260
[  681.774991]  [] ? sort_range+0x40/0x40
[  681.774992]  [] kthread+0xe4/0x100
[  681.774994]  [] ? kthread_worker_fn+0x170/0x170
[  681.774995]  [] ret_from_fork+0x3e/0x70

mq/mqprio have their own ways to report qlen/drops by folding stats on
all their queues, with appropriate locking.

A second problem is that qdisc_tree_decrease_qlen() calls qdisc_lookup()
without proper locking : concurrent qdisc updates could corrupt the list
that qdisc_match_from_root() parses to find a qdisc given its handle.

Fix first problem adding a TCQ_F_NOPARENT qdisc flag that
qdisc_tree_decrease_qlen() can use to abort its tree traversal,
as soon as it meets a mq/mqprio qdisc children.

Second problem can be fixed by RCU protection.
Qdisc are already freed after RCU grace period, so qdisc_list_add() and
qdisc_list_del() simply have to use appropriate rcu list variants.

A future patch will add a per struct netdev_queue list anchor, so that
qdisc_tree_decrease_qlen() can have more efficient lookups.

Reported-by: Daniele Fucini 
Signed-off-by: Eric Dumazet 
Cc: Cong Wang 
Cc: Jamal Hadi Salim 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

openvswitch: fix hangup on vxlan/gre/geneve device deletion

2015-12-15T05:41:04+00:00

[ Upstream commit 13175303024c8f4cd09e51079a8fcbbe572111ec ]

Each openvswitch tunnel vport (vxlan,gre,geneve) holds a reference
to the underlying tunnel device, but never released it when such
device is deleted.
Deleting the underlying device via the ip tool cause the kernel to
hangup in the netdev_wait_allrefs() loop.
This commit ensure that on device unregistration dp_detach_port_notify()
is called for all vports that hold the device reference, properly
releasing it.

Fixes: 614732eaa12d ("openvswitch: Use regular VXLAN net_device device")
Fixes: b2acd1dc3949 ("openvswitch: Use regular GRE net_device instead of vport")
Fixes: 6b001e682e90 ("openvswitch: Use Geneve device.")
Signed-off-by: Paolo Abeni 
Acked-by: Flavio Leitner 
Acked-by: Pravin B Shelar 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: sctp: implement sctp_v6_destroy_sock()

2015-12-15T05:41:04+00:00

[ Upstream commit 602dd62dfbda3e63a2d6a3cbde953ebe82bf5087 ]

Dmitry Vyukov reported a memory leak using IPV6 SCTP sockets.

We need to call inet6_destroy_sock() to properly release
inet6 specific fields.

Reported-by: Dmitry Vyukov 
Signed-off-by: Eric Dumazet 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net/neighbour: fix crash at dumping device-agnostic proxy entries

2015-12-15T05:41:04+00:00

[ Upstream commit 6adc5fd6a142c6e2c80574c1db0c7c17dedaa42e ]

Proxy entries could have null pointer to net-device.

Signed-off-by: Konstantin Khlebnikov 
Fixes: 84920c1420e2 ("net: Allow ipv6 proxies and arp proxies be shown with iproute2")
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: add complete rcu protection around np->opt

2015-12-15T05:41:04+00:00

[ Upstream commit 45f6fad84cc305103b28d73482b344d7f5b76f39 ]

This patch addresses multiple problems :

UDP/RAW sendmsg() need to get a stable struct ipv6_txoptions
while socket is not locked : Other threads can change np->opt
concurrently. Dmitry posted a syzkaller
(http://github.com/google/syzkaller) program desmonstrating
use-after-free.

Starting with TCP/DCCP lockless listeners, tcp_v6_syn_recv_sock()
and dccp_v6_request_recv_sock() also need to use RCU protection
to dereference np->opt once (before calling ipv6_dup_options())

This patch adds full RCU protection to np->opt

Reported-by: Dmitry Vyukov 
Signed-off-by: Eric Dumazet 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

RDS: fix race condition when sending a message on unbound socket

2015-12-15T05:41:03+00:00

[ Upstream commit 8c7188b23474cca017b3ef354c4a58456f68303a ]

Sasha's found a NULL pointer dereference in the RDS connection code when
sending a message to an apparently unbound socket.  The problem is caused
by the code checking if the socket is bound in rds_sendmsg(), which checks
the rs_bound_addr field without taking a lock on the socket.  This opens a
race where rs_bound_addr is temporarily set but where the transport is not
in rds_bind(), leading to a NULL pointer dereference when trying to
dereference 'trans' in __rds_conn_create().

Vegard wrote a reproducer for this issue, so kindly ask him to share if
you're interested.

I cannot reproduce the NULL pointer dereference using Vegard's reproducer
with this patch, whereas I could without.

Complete earlier incomplete fix to CVE-2015-6937:

  74e98eb08588 ("RDS: verify the underlying transport exists before creating a connection")

Cc: David S. Miller 
Cc: stable@vger.kernel.org

Reviewed-by: Vegard Nossum 
Reviewed-by: Sasha Levin 
Acked-by: Santosh Shilimkar 
Signed-off-by: Quentin Casasnovas 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: distinguish frag queues by device for multicast and link-local packets

2015-12-15T05:41:03+00:00

[ Upstream commit 264640fc2c5f4f913db5c73fa3eb1ead2c45e9d7 ]

If a fragmented multicast packet is received on an ethernet device which
has an active macvlan on top of it, each fragment is duplicated and
received both on the underlying device and the macvlan. If some
fragments for macvlan are processed before the whole packet for the
underlying device is reassembled, the "overlapping fragments" test in
ip6_frag_queue() discards the whole fragment queue.

To resolve this, add device ifindex to the search key and require it to
match reassembling multicast packets and packets to link-local
addresses.

Note: similar patch has been already submitted by Yoshifuji Hideaki in

  http://patchwork.ozlabs.org/patch/220979/

but got lost and forgotten for some reason.

Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tipc: fix error handling of expanding buffer headroom

2015-12-15T05:41:03+00:00

[ Upstream commit 7098356baca723513e97ca0020df4e18bc353be3 ]

Coverity says:
*** CID 1338065:  Error handling issues  (CHECKED_RETURN)
/net/tipc/udp_media.c: 162 in tipc_udp_send_msg()
156             struct udp_media_addr *dst = (struct udp_media_addr *)&dest->value;
157             struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
158             struct sk_buff *clone;
159             struct rtable *rt;
160
161             if (skb_headroom(skb) < UDP_MIN_HEADROOM)
>>>     CID 1338065:  Error handling issues  (CHECKED_RETURN)
>>>     Calling "pskb_expand_head" without checking return value (as is done elsewhere 51 out of 56
+times).
162                     pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
163
164             clone = skb_clone(skb, GFP_ATOMIC);
165             skb_set_inner_protocol(clone, htons(ETH_P_TIPC));
166             ub = rcu_dereference_rtnl(b->media_ptr);
167             if (!ub) {

When expanding buffer headroom over udp tunnel with pskb_expand_head(),
it's unfortunate that we don't check its return value. As a result, if
the function returns an error code due to the lack of memory, it may
cause unpredictable consequence as we unconditionally consider that
it's always successful.

Fixes: e53567948f82 ("tipc: conditionally expand buffer headroom over udp tunnel")
Reported-by: 
Cc: Stephen Hemminger 
Signed-off-by: Ying Xue 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ip6mr: fix static mfc/dev leaks on table destruction

2015-12-15T05:41:02+00:00

[ Upstream commit 4c6980462f32b4f282c5d8e5f7ea8070e2937725 ]

Similar to ipv4, 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. Make sure that
everything is cleaned up on netns destruction.

Fixes: 8229efdaef1e ("netns: ip6mr: enable namespace support in ipv6 multicast forwarding code")
CC: Benjamin Thery 
Signed-off-by: Nikolay Aleksandrov 
Reviewed-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ipmr: fix static mfc/dev leaks on table destruction

2015-12-15T05:41:02+00:00

[ Upstream commit 0e615e9601a15efeeb8942cf7cd4dadba0c8c5a7 ]

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 
Signed-off-by: Greg Kroah-Hartman