Anoob Soman fe41cfb48f packet: Do not call fanout_release from atomic contexts ... [ Upstream commit 2bd624b4611ffee36422782d16e1c944d1351e98 ] Commit 6664498280cf ("packet: call fanout_release, while UNREGISTERING a netdev"), unfortunately, introduced the following issues. 1. calling mutex_lock(&fanout_mutex) (fanout_release()) from inside rcu_read-side critical section. rcu_read_lock disables preemption, most often, which prohibits calling sleeping functions. [ ] include/linux/rcupdate.h:560 Illegal context switch in RCU read-side critical section! [ ] [ ] rcu_scheduler_active = 1, debug_locks = 0 [ ] 4 locks held by ovs-vswitchd/1969: [ ] #0: (cb_lock){++++++}, at: [<ffffffff8158a6c9>] genl_rcv+0x19/0x40 [ ] #1: (ovs_mutex){+.+.+.}, at: [<ffffffffa04878ca>] ovs_vport_cmd_del+0x4a/0x100 [openvswitch] [ ] #2: (rtnl_mutex){+.+.+.}, at: [<ffffffff81564157>] rtnl_lock+0x17/0x20 [ ] #3: (rcu_read_lock){......}, at: [<ffffffff81614165>] packet_notifier+0x5/0x3f0 [ ] [ ] Call Trace: [ ] [<ffffffff813770c1>] dump_stack+0x85/0xc4 [ ] [<ffffffff810c9077>] lockdep_rcu_suspicious+0x107/0x110 [ ] [<ffffffff810a2da7>] ___might_sleep+0x57/0x210 [ ] [<ffffffff810a2fd0>] __might_sleep+0x70/0x90 [ ] [<ffffffff8162e80c>] mutex_lock_nested+0x3c/0x3a0 [ ] [<ffffffff810de93f>] ? vprintk_default+0x1f/0x30 [ ] [<ffffffff81186e88>] ? printk+0x4d/0x4f [ ] [<ffffffff816106dd>] fanout_release+0x1d/0xe0 [ ] [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0 2. calling mutex_lock(&fanout_mutex) inside spin_lock(&po->bind_lock). "sleeping function called from invalid context" [ ] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620 [ ] in_atomic(): 1, irqs_disabled(): 0, pid: 1969, name: ovs-vswitchd [ ] INFO: lockdep is turned off. [ ] Call Trace: [ ] [<ffffffff813770c1>] dump_stack+0x85/0xc4 [ ] [<ffffffff810a2f52>] ___might_sleep+0x202/0x210 [ ] [<ffffffff810a2fd0>] __might_sleep+0x70/0x90 [ ] [<ffffffff8162e80c>] mutex_lock_nested+0x3c/0x3a0 [ ] [<ffffffff816106dd>] fanout_release+0x1d/0xe0 [ ] [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0 3. calling dev_remove_pack(&fanout->prot_hook), from inside spin_lock(&po->bind_lock) or rcu_read-side critical-section. dev_remove_pack() -> synchronize_net(), which might sleep. [ ] BUG: scheduling while atomic: ovs-vswitchd/1969/0x00000002 [ ] INFO: lockdep is turned off. [ ] Call Trace: [ ] [<ffffffff813770c1>] dump_stack+0x85/0xc4 [ ] [<ffffffff81186274>] __schedule_bug+0x64/0x73 [ ] [<ffffffff8162b8cb>] __schedule+0x6b/0xd10 [ ] [<ffffffff8162c5db>] schedule+0x6b/0x80 [ ] [<ffffffff81630b1d>] schedule_timeout+0x38d/0x410 [ ] [<ffffffff810ea3fd>] synchronize_sched_expedited+0x53d/0x810 [ ] [<ffffffff810ea6de>] synchronize_rcu_expedited+0xe/0x10 [ ] [<ffffffff8154eab5>] synchronize_net+0x35/0x50 [ ] [<ffffffff8154eae3>] dev_remove_pack+0x13/0x20 [ ] [<ffffffff8161077e>] fanout_release+0xbe/0xe0 [ ] [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0 4. fanout_release() races with calls from different CPU. To fix the above problems, remove the call to fanout_release() under rcu_read_lock(). Instead, call __dev_remove_pack(&fanout->prot_hook) and netdev_run_todo will be happy that &dev->ptype_specific list is empty. In order to achieve this, I moved dev_{add,remove}_pack() out of fanout_{add,release} to __fanout_{link,unlink}. So, call to {,__}unregister_prot_hook() will make sure fanout->prot_hook is removed as well. Fixes: 6664498280cf ("packet: call fanout_release, while UNREGISTERING a netdev") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Anoob Soman <anoob.soman@citrix.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2017-02-26 11:07:50 +01:00
..
6lowpan	6lowpan: put mcast compression in an own function	2015-10-21 00:49:25 +02:00
9p	IB/cma: Add support for network namespaces	2015-10-28 12:32:48 -04:00
802
8021q	net: add recursion limit to GRO	2016-11-15 07:46:38 +01:00
appletalk
atm	atm: deal with setting entry before mkip was called	2015-09-17 22:13:32 -07:00
ax25	ax25: Fix segfault after sock connection timeout	2017-02-04 09:45:09 +01:00
batman-adv	batman-adv: Check for alloc errors when preparing TT local data	2016-12-15 08:49:23 -08:00
bluetooth	Bluetooth: Fix l2cap_sock_setsockopt() with optname BT_RCVMTU	2016-08-20 18:09:19 +02:00
bridge	bridge: netlink: call br_changelink() during br_dev_newlink()	2017-02-04 09:45:09 +01:00
caif	net: caif: fix misleading indentation	2016-09-30 10:18:35 +02:00
can	can: Fix kernel panic at security_sock_rcv_skb	2017-02-18 16:39:26 +01:00
ceph	libceph: verify authorize reply on connect	2017-01-09 08:07:52 +01:00
core	net: use a work queue to defer net_disable_timestamp() work	2017-02-18 16:39:26 +01:00
dcb	net/dcb: make dcbnl.c explicitly non-modular	2015-10-09 07:52:27 -07:00
dccp	net/dccp: fix use-after-free in dccp_invalid_packet	2016-12-10 19:07:24 +01:00
decnet	decnet: Do not build routes to devices without decnet private data.	2016-05-18 17:06:35 -07:00
dns_resolver	net: dns_resolver: convert time_t to time64_t	2015-11-18 16:27:46 -05:00
dsa	net: dsa: Bring back device detaching in dsa_slave_suspend()	2017-02-04 09:45:10 +01:00
ethernet	net: introduce device min_header_len	2017-02-18 16:39:27 +01:00
hsr	net/hsr: fix a warning message	2015-11-23 14:56:15 -05:00
ieee802154	net: fix percpu memory leaks	2015-11-02 22:47:14 -05:00
ipv4	ping: fix a null pointer dereference	2017-02-18 16:39:27 +01:00
ipv6	sit: fix a double free on error path	2017-02-18 16:39:27 +01:00
ipx
irda	net/irda: handle iriap_register_lsap() allocation failure	2016-09-30 10:18:36 +02:00
iucv	af_iucv: Validate socket address length in iucv_sock_bind()	2016-03-03 15:07:03 -08:00
key	af_key: fix two typos	2015-10-23 03:05:19 -07:00
l2tp	l2tp: do not use udp_ioctl()	2017-02-18 16:39:28 +01:00
l3mdev	net: Add netif_is_l3_slave	2015-10-07 04:27:43 -07:00
lapb
llc	net/llc: avoid BUG_ON() in skb_orphan()	2017-02-26 11:07:49 +01:00
mac80211	mac80211: Fix adding of mesh vendor IEs	2017-02-14 15:22:51 -08:00
mac802154	mac802154: llsec: use kzfree	2015-10-21 00:49:24 +02:00
mpls	mpls: find_outdev: check for err ptr in addition to NULL check	2016-04-20 15:42:07 +09:00
netfilter	netfilter: nft_dynset: fix element timeout for HZ != 1000	2016-11-26 09:54:54 +01:00
netlabel	netlabel: add address family checks to netlbl_{sock,req}_delattr()	2016-08-20 18:09:22 +02:00
netlink	netlink: Do not schedule work from sk_destruct	2016-12-10 19:07:23 +01:00
netrom
nfc	net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA	2015-12-01 15:45:05 -05:00
openvswitch	openvswitch: maintain correct checksum state in conntrack actions	2017-02-04 09:45:09 +01:00
packet	packet: Do not call fanout_release from atomic contexts	2017-02-26 11:07:50 +01:00
phonet	phonet: properly unshare skbs in phonet_rcv()	2016-01-31 11:29:00 -08:00
rds	rds: fix an infoleak in rds_inc_info_copy	2016-09-15 08:27:51 +02:00
rfkill	rfkill: fix rfkill_fop_read wait_event usage	2016-03-03 15:07:26 -08:00
rose
rxrpc	net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA	2015-12-01 15:45:05 -05:00
sched	net, sched: fix soft lockup in tc_classify	2017-01-15 13:41:34 +01:00
sctp	sctp: avoid BUG_ON on sctp_wait_for_sndbuf	2017-02-18 16:39:27 +01:00
sunrpc	svcrpc: fix oops in absence of krb5 module	2017-02-09 08:02:45 +01:00
switchdev	switchdev: pass pointer to fib_info instead of copy	2016-06-24 10:18:16 -07:00
tipc	tipc: fix NULL pointer dereference in shutdown()	2016-09-30 10:18:36 +02:00
unix	af_unix: move unix_mknod() out of bindlock	2017-02-04 09:45:09 +01:00
vmw_vsock	VSOCK: do not disconnect socket when peer has shutdown SEND only	2016-05-18 17:06:41 -07:00
wimax	net:wimax: Fix doucble word "the the" in networking.xml	2015-08-09 22:43:52 -07:00
wireless	nl80211: fix sched scan netlink socket owner destruction	2017-01-19 20:17:20 +01:00
x25	net: fix a kernel infoleak in x25 module	2016-05-18 17:06:43 -07:00
xfrm	xfrm: Fix crash observed during device unregistration and decryption	2016-04-20 15:42:05 +09:00
compat.c
Kconfig	net: Introduce L3 Master device abstraction	2015-09-29 20:40:32 -07:00
Makefile	net: Introduce L3 Master device abstraction	2015-09-29 20:40:32 -07:00
socket.c	sock: fix sendmmsg for partial sendmsg	2016-11-21 10:06:40 +01:00
sysctl_net.c	net: Use ns_capable_noaudit() when determining net sysctl permissions	2016-09-15 08:27:50 +02:00