linux/net/core
Craig Gallek b922622ec6 sock_diag: don't broadcast kernel sockets
Kernel sockets do not hold a reference for the network namespace to
which they point.  Socket destruction broadcasting relies on the
network namespace and will cause the splat below when a kernel socket
is destroyed.

This fix simply ignores kernel sockets when they are destroyed.

Reported as:
general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU: 1 PID: 9130 Comm: kworker/1:1 Not tainted 4.1.0-gelk-debug+ #1
Workqueue: sock_diag_events sock_diag_broadcast_destroy_work
Stack:
 ffff8800b9c586c0 ffff8800b9c586c0 ffff8800ac4692c0 ffff8800936d4a90
 ffff8800352efd38 ffffffff8469a93e ffff8800352efd98 ffffffffc09b9b90
 ffff8800352efd78 ffff8800ac4692c0 ffff8800b9c586c0 ffff8800831b6ab8
Call Trace:
 [<ffffffff8469a93e>] ? mutex_unlock+0xe/0x10
 [<ffffffffc09b9b90>] ? inet_diag_handler_get_info+0x110/0x1fb [inet_diag]
 [<ffffffff845c868d>] netlink_broadcast+0x1d/0x20
 [<ffffffff8469a93e>] ? mutex_unlock+0xe/0x10
 [<ffffffff845b2bf5>] sock_diag_broadcast_destroy_work+0xd5/0x160
 [<ffffffff8408ea97>] process_one_work+0x147/0x420
 [<ffffffff8408f0f9>] worker_thread+0x69/0x470
 [<ffffffff8409fda3>] ? preempt_count_sub+0xa3/0xf0
 [<ffffffff8408f090>] ? rescuer_thread+0x320/0x320
 [<ffffffff84093cd7>] kthread+0x107/0x120
 [<ffffffff84093bd0>] ? kthread_create_on_node+0x1b0/0x1b0
 [<ffffffff8469d31f>] ret_from_fork+0x3f/0x70
 [<ffffffff84093bd0>] ? kthread_create_on_node+0x1b0/0x1b0

Tested:
  Using a debug kernel while 'ss -E' is running:
  ip netns add test-ns
  ip netns delete test-ns

Fixes: eb4cb00852 sock_diag: define destruction multicast groups
Fixes: 26abe14379 net: Modify sk_alloc to not reference count the
  netns of kernel sockets.
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>

Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-30 10:00:26 -07:00
..
datagram.c new helper: msg_data_left() 2015-04-11 15:53:35 -04:00
dev_addr_lists.c net: fix spelling for synchronized 2014-11-18 15:26:32 -05:00
dev_ioctl.c dev_ioctl: use sizeof(x) instead of sizeof x 2014-11-18 15:27:32 -05:00
dev.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-06-08 20:06:56 -07:00
drop_monitor.c net: Replace get_cpu_var through this_cpu_ptr 2014-08-26 13:45:47 -04:00
dst.c dst: no need to take reference on DST_NOCACHE dsts 2014-12-09 16:08:17 -05:00
ethtool.c net/ethtool: Add current supported tunable options 2015-06-11 00:36:37 -07:00
fib_rules.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-04-06 22:34:15 -04:00
filter.c bpf: disallow bpf tc programs access current->pid,uid 2015-06-15 20:51:20 -07:00
flow_dissector.c flow_dissector: Pre-initialize ip_proto in __skb_flow_dissect() 2015-06-28 16:53:54 -07:00
flow.c flowcache: Fix kernel panic in flow_cache_flush_task 2015-02-05 14:38:53 -08:00
gen_estimator.c net: sched: make bstats per cpu and estimator RCU safe 2014-09-30 01:02:26 -04:00
gen_stats.c gen_stats.c: Duplicate xstats buffer for later use 2015-02-19 15:45:53 -05:00
link_watch.c dev: introduce dev_get_iflink() 2015-04-02 14:04:59 -04:00
Makefile net: bury net/core/iovec.c - nothing in there is used anymore 2015-02-04 01:34:15 -05:00
neighbour.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-06-24 02:58:51 -07:00
net_namespace.c netns: make nsid_lock per net 2015-05-17 23:41:11 -04:00
net-procfs.c rps: selective flow shedding during softnet overflow 2013-05-20 13:48:04 -07:00
net-sysfs.c switchdev: don't use anonymous union on switchdev attr/obj structs 2015-05-13 14:20:59 -04:00
net-sysfs.h net: netdev_kobject_init: annotate with __init 2014-01-05 20:27:54 -05:00
net-traces.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
netclassid_cgroup.c cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes 2014-07-15 11:05:09 -04:00
netevent.c netevent: remove automatic variable in register_netevent_notifier() 2015-05-31 00:03:21 -07:00
netpoll.c net: rename vlan_tx_* helpers since "tx" is misleading there 2015-01-13 17:51:08 -05:00
netprio_cgroup.c cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes 2014-07-15 11:05:09 -04:00
pktgen.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2015-06-24 16:49:49 -07:00
ptp_classifier.c net: filter: split 'struct sk_filter' into socket and bpf parts 2014-08-02 15:03:58 -07:00
request_sock.c net: convert syn_wait_lock to a spinlock 2015-03-23 16:52:26 -04:00
rtnetlink.c switchdev; add VLAN support for port's bridge_getlink 2015-06-23 06:56:18 -07:00
scm.c net: introduce helper macro for_each_cmsghdr 2014-12-10 22:41:55 -05:00
secure_seq.c net: remove a sparse error in secure_dccpv6_sequence_number() 2015-05-25 22:55:37 -04:00
skbuff.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-06-13 23:56:52 -07:00
sock_diag.c sock_diag: define destruction multicast groups 2015-06-15 19:49:22 -07:00
sock.c sock_diag: don't broadcast kernel sockets 2015-06-30 10:00:26 -07:00
stream.c tcp: set SOCK_NOSPACE under memory pressure 2015-05-09 17:38:36 -04:00
sysctl_net_core.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-03-20 18:51:09 -04:00
timestamping.c net-timestamp: Make the clone operation stand-alone from phy timestamping 2014-09-05 17:43:45 -07:00
tso.c net: tso: fix unaligned access to crafted TCP header in helper API 2014-10-22 12:52:55 -04:00
utils.c net: fix inet_proto_csum_replace4() sparse errors 2015-05-25 22:56:47 -04:00