linux-stable.git/net, branch v3.16.78

sctp: Fix the link time qualifier of 'sctp_ctrlsock_exit()'

2019-11-22T15:57:29+00:00

commit b456d72412ca8797234449c25815e82f4e1426c0 upstream.

The '.exit' functions from 'pernet_operations' structure should be marked
as __net_exit, not __net_init.

Fixes: 8e2d61e0aed2 ("sctp: fix race on protocol/netns initialization")
Signed-off-by: Christophe JAILLET 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

net: Fix null de-reference of device refcount

2019-11-22T15:57:29+00:00

commit 10cc514f451a0f239aa34f91bc9dc954a9397840 upstream.

In event of failure during register_netdevice, free_netdev is
invoked immediately. free_netdev assumes that all the netdevice
refcounts have been dropped prior to it being called and as a
result frees and clears out the refcount pointer.

However, this is not necessarily true as some of the operations
in the NETDEV_UNREGISTER notifier handlers queue RCU callbacks for
invocation after a grace period. The IPv4 callback in_dev_rcu_put
tries to access the refcount after free_netdev is called which
leads to a null de-reference-

44837.761523:   <6> Unable to handle kernel paging request at
                    virtual address 0000004a88287000
44837.761651:   <2> pc : in_dev_finish_destroy+0x4c/0xc8
44837.761654:   <2> lr : in_dev_finish_destroy+0x2c/0xc8
44837.762393:   <2> Call trace:
44837.762398:   <2>  in_dev_finish_destroy+0x4c/0xc8
44837.762404:   <2>  in_dev_rcu_put+0x24/0x30
44837.762412:   <2>  rcu_nocb_kthread+0x43c/0x468
44837.762418:   <2>  kthread+0x118/0x128
44837.762424:   <2>  ret_from_fork+0x10/0x1c

Fix this by waiting for the completion of the call_rcu() in
case of register_netdevice errors.

Fixes: 93ee31f14f6f ("[NET]: Fix free_netdev on register_netdev failure.")
Cc: Sean Tranchetti 
Signed-off-by: Subash Abhinov Kasiviswanathan 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

ipv6: Fix the link time qualifier of 'ping_v6_proc_exit_net()'

2019-11-22T15:57:28+00:00

commit d23dbc479a8e813db4161a695d67da0e36557846 upstream.

The '.exit' functions from 'pernet_operations' structure should be marked
as __net_exit, not __net_init.

Fixes: d862e5461423 ("net: ipv6: Implement /proc/net/icmp6.")
Signed-off-by: Christophe JAILLET 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

tcp: fix tcp_ecn_withdraw_cwr() to clear TCP_ECN_QUEUE_CWR

2019-11-22T15:57:28+00:00

commit af38d07ed391b21f7405fa1f936ca9686787d6d2 upstream.

Fix tcp_ecn_withdraw_cwr() to clear the correct bit:
TCP_ECN_QUEUE_CWR.

Rationale: basically, TCP_ECN_DEMAND_CWR is a bit that is purely about
the behavior of data receivers, and deciding whether to reflect
incoming IP ECN CE marks as outgoing TCP th->ece marks. The
TCP_ECN_QUEUE_CWR bit is purely about the behavior of data senders,
and deciding whether to send CWR. The tcp_ecn_withdraw_cwr() function
is only called from tcp_undo_cwnd_reduction() by data senders during
an undo, so it should zero the sender-side state,
TCP_ECN_QUEUE_CWR. It does not make sense to stop the reflection of
incoming CE bits on incoming data packets just because outgoing
packets were spuriously retransmitted.

The bug has been reproduced with packetdrill to manifest in a scenario
with RFC3168 ECN, with an incoming data packet with CE bit set and
carrying a TCP timestamp value that causes cwnd undo. Before this fix,
the IP CE bit was ignored and not reflected in the TCP ECE header bit,
and sender sent a TCP CWR ('W') bit on the next outgoing data packet,
even though the cwnd reduction had been undone.  After this fix, the
sender properly reflects the CE bit and does not set the W bit.

Note: the bug actually predates 2005 git history; this Fixes footer is
chosen to be the oldest SHA1 I have tested (from Sep 2007) for which
the patch applies cleanly (since before this commit the code was in a
.h file).

Fixes: bdf1ee5d3bd3 ("[TCP]: Move code from tcp_ecn.h to tcp*.c and tcp.h & remove it")
Signed-off-by: Neal Cardwell 
Acked-by: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Cc: Eric Dumazet 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

sch_hhf: ensure quantum and hhf_non_hh_weight are non-zero

2019-11-22T15:57:27+00:00

commit d4d6ec6dac07f263f06d847d6f732d6855522845 upstream.

In case of TCA_HHF_NON_HH_WEIGHT or TCA_HHF_QUANTUM is zero,
it would make no progress inside the loop in hhf_dequeue() thus
kernel would get stuck.

Fix this by checking this corner case in hhf_change().

Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Reported-by: syzbot+bc6297c11f19ee807dc2@syzkaller.appspotmail.com
Reported-by: syzbot+041483004a7f45f1f20a@syzkaller.appspotmail.com
Reported-by: syzbot+55be5f513bed37fc4367@syzkaller.appspotmail.com
Cc: Jamal Hadi Salim 
Cc: Jiri Pirko 
Cc: Terry Lam 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

sctp: use transport pf_retrans in sctp_do_8_2_transport_strike

2019-11-22T15:57:26+00:00

commit 10eb56c582c557c629271f1ee31e15e7a9b2558b upstream.

Transport should use its own pf_retrans to do the error_count
check, instead of asoc's. Otherwise, it's meaningless to make
pf_retrans per transport.

Fixes: 5aa93bcf66f4 ("sctp: Implement quick failover draft from tsvwg")
Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

mld: fix memory leak in mld_del_delrec()

2019-11-22T15:57:24+00:00

commit a84d016479896b5526a2cc54784e6ffc41c9d6f6 upstream.

Similar to the fix done for IPv4 in commit e5b1c6c6277d
("igmp: fix memory leak in igmpv3_del_delrec()"), we need to
make sure mca_tomb and mca_sources are not blindly overwritten.

Using swap() then a call to ip6_mc_clear_src() will take care
of the missing free.

BUG: memory leak
unreferenced object 0xffff888117d9db00 (size 64):
  comm "syz-executor247", pid 6918, jiffies 4294943989 (age 25.350s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 fe 88 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000005b463030>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<000000005b463030>] slab_post_alloc_hook mm/slab.h:522 [inline]
    [<000000005b463030>] slab_alloc mm/slab.c:3319 [inline]
    [<000000005b463030>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
    [<00000000939cbf94>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000939cbf94>] kzalloc include/linux/slab.h:748 [inline]
    [<00000000939cbf94>] ip6_mc_add1_src net/ipv6/mcast.c:2236 [inline]
    [<00000000939cbf94>] ip6_mc_add_src+0x31f/0x420 net/ipv6/mcast.c:2356
    [<00000000d8972221>] ip6_mc_source+0x4a8/0x600 net/ipv6/mcast.c:449
    [<000000002b203d0d>] do_ipv6_setsockopt.isra.0+0x1b92/0x1dd0 net/ipv6/ipv6_sockglue.c:748
    [<000000001f1e2d54>] ipv6_setsockopt+0x89/0xd0 net/ipv6/ipv6_sockglue.c:944
    [<00000000c8f7bdf9>] udpv6_setsockopt+0x4e/0x90 net/ipv6/udp.c:1558
    [<000000005a9a0c5e>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3139
    [<00000000910b37b2>] __sys_setsockopt+0x10f/0x220 net/socket.c:2084
    [<00000000e9108023>] __do_sys_setsockopt net/socket.c:2100 [inline]
    [<00000000e9108023>] __se_sys_setsockopt net/socket.c:2097 [inline]
    [<00000000e9108023>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2097
    [<00000000f4818160>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296
    [<000000008d367e8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when set link down")
Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

batman-adv: Only read OGM tvlv_len after buffer len check

2019-11-22T15:57:20+00:00

commit a15d56a60760aa9dbe26343b9a0ac5228f35d445 upstream.

Multiple batadv_ogm_packet can be stored in an skbuff. The functions
batadv_iv_ogm_send_to_if()/batadv_iv_ogm_receive() use
batadv_iv_ogm_aggr_packet() to check if there is another additional
batadv_ogm_packet in the skb or not before they continue processing the
packet.

The length for such an OGM is BATADV_OGM_HLEN +
batadv_ogm_packet->tvlv_len. The check must first check that at least
BATADV_OGM_HLEN bytes are available before it accesses tvlv_len (which is
part of the header. Otherwise it might try read outside of the currently
available skbuff to get the content of tvlv_len.

Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure")
Reported-by: syzbot+355cab184197dbbfa384@syzkaller.appspotmail.com
Signed-off-by: Sven Eckelmann 
Acked-by: Antonio Quartulli 
Signed-off-by: Simon Wunderlich 
[bwh: Backported to 3.16:
 - Drop kernel-doc change
 - Adjust context]
Signed-off-by: Ben Hutchings

Revert "cfg80211: fix processing world regdomain when non modular"

2019-11-22T15:57:18+00:00

commit 0d31d4dbf38412f5b8b11b4511d07b840eebe8cb upstream.

This reverts commit 96cce12ff6e0 ("cfg80211: fix processing world
regdomain when non modular").

Re-triggering a reg_process_hint with the last request on all events,
can make the regulatory domain fail in case of multiple WiFi modules. On
slower boards (espacially with mdev), enumeration of the WiFi modules
can end up in an intersected regulatory domain, and user cannot set it
with 'iw reg set' anymore.

This is happening, because:
- 1st module enumerates, queues up a regulatory request
- request gets processed by __reg_process_hint_driver():
  - checks if previous was set by CORE -> yes
    - checks if regulator domain changed -> yes, from '00' to e.g. 'US'
      -> sends request to the 'crda'
- 2nd module enumerates, queues up a regulator request (which triggers
  the reg_todo() work)
- reg_todo() -> reg_process_pending_hints() sees, that the last request
  is not processed yet, so it tries to process it again.
  __reg_process_hint driver() will run again, and:
  - checks if the last request's initiator was the core -> no, it was
    the driver (1st WiFi module)
  - checks, if the previous initiator was the driver -> yes
    - checks if the regulator domain changed -> yes, it was '00' (set by
      core, and crda call did not return yet), and should be changed to 'US'

------> __reg_process_hint_driver calls an intersect

Besides, the reg_process_hint call with the last request is meaningless
since the crda call has a timeout work. If that timeout expires, the
first module's request will lost.

Fixes: 96cce12ff6e0 ("cfg80211: fix processing world regdomain when non modular")
Signed-off-by: Robert Hodaszi 
Link: https://lore.kernel.org/r/20190614131600.GA13897@a1-hr
Signed-off-by: Johannes Berg 
Signed-off-by: Ben Hutchings

net/packet: fix race in tpacket_snd()

2019-11-22T15:57:17+00:00

commit 32d3182cd2cd29b2e7e04df7b0db350fbe11289f upstream.

packet_sendmsg() checks tx_ring.pg_vec to decide
if it must call tpacket_snd().

Problem is that the check is lockless, meaning another thread
can issue a concurrent setsockopt(PACKET_TX_RING ) to flip
tx_ring.pg_vec back to NULL.

Given that tpacket_snd() grabs pg_vec_lock mutex, we can
perform the check again to solve the race.

syzbot reported :

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 11429 Comm: syz-executor394 Not tainted 5.3.0-rc4+ #101
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:packet_lookup_frame+0x8d/0x270 net/packet/af_packet.c:474
Code: c1 ee 03 f7 73 0c 80 3c 0e 00 0f 85 cb 01 00 00 48 8b 0b 89 c0 4c 8d 24 c1 48 b8 00 00 00 00 00 fc ff df 4c 89 e1 48 c1 e9 03 <80> 3c 01 00 0f 85 94 01 00 00 48 8d 7b 10 4d 8b 3c 24 48 b8 00 00
RSP: 0018:ffff88809f82f7b8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff8880a45c7030 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 1ffff110148b8e06 RDI: ffff8880a45c703c
RBP: ffff88809f82f7e8 R08: ffff888087aea200 R09: fffffbfff134ae50
R10: fffffbfff134ae4f R11: ffffffff89a5727f R12: 0000000000000000
R13: 0000000000000001 R14: ffff8880a45c6ac0 R15: 0000000000000000
FS:  00007fa04716f700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa04716edb8 CR3: 0000000091eb4000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 packet_current_frame net/packet/af_packet.c:487 [inline]
 tpacket_snd net/packet/af_packet.c:2667 [inline]
 packet_sendmsg+0x590/0x6250 net/packet/af_packet.c:2975
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:657
 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2311
 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg net/socket.c:2439 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2439
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 69e3c75f4d54 ("net: TX_RING and packet mmap")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings