linux/net
subashab@codeaurora.org 16186a82de ipv6: addrconf: Fix recursive spin lock call
A rcu stall with the following backtrace was seen on a system with
forwarding, optimistic_dad and use_optimistic set. To reproduce,
set these flags and allow ipv6 autoconf.

This occurs because the device write_lock is acquired while already
holding the read_lock. Back trace below -

INFO: rcu_preempt self-detected stall on CPU { 1}  (t=2100 jiffies
 g=3992 c=3991 q=4471)
<6> Task dump for CPU 1:
<2> kworker/1:0     R  running task    12168    15   2 0x00000002
<2> Workqueue: ipv6_addrconf addrconf_dad_work
<6> Call trace:
<2> [<ffffffc000084da8>] el1_irq+0x68/0xdc
<2> [<ffffffc000cc4e0c>] _raw_write_lock_bh+0x20/0x30
<2> [<ffffffc000bc5dd8>] __ipv6_dev_ac_inc+0x64/0x1b4
<2> [<ffffffc000bcbd2c>] addrconf_join_anycast+0x9c/0xc4
<2> [<ffffffc000bcf9f0>] __ipv6_ifa_notify+0x160/0x29c
<2> [<ffffffc000bcfb7c>] ipv6_ifa_notify+0x50/0x70
<2> [<ffffffc000bd035c>] addrconf_dad_work+0x314/0x334
<2> [<ffffffc0000b64c8>] process_one_work+0x244/0x3fc
<2> [<ffffffc0000b7324>] worker_thread+0x2f8/0x418
<2> [<ffffffc0000bb40c>] kthread+0xe0/0xec

v2: do addrconf_dad_kick inside read lock and then acquire write
lock for ipv6_ifa_notify as suggested by Eric

Fixes: 7fd2561e4e ("net: ipv6: Add a sysctl to make optimistic
addresses useful candidates")

Cc: Eric Dumazet <edumazet@google.com>
Cc: Erik Kline <ek@google.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06 03:08:15 -05:00
..
6lowpan 6lowpan: fix debugfs interface entry name 2015-12-20 08:21:00 +01:00
9p Rework and error handling fixes, primarily in the fscatch and fd transports. 2016-01-24 12:39:09 -08:00
802
8021q net: Rename NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK 2015-12-15 16:50:08 -05:00
appletalk
atm net: Generalise wq_has_sleeper helper 2015-11-30 14:47:33 -05:00
ax25 net: add validation for the socket syscall protocol argument 2015-12-14 16:09:30 -05:00
batman-adv batman-adv: Drop immediate orig_node free function 2016-01-16 22:50:00 +08:00
bluetooth Bluetooth: Fix incorrect removing of IRKs 2016-01-29 11:47:24 +01:00
bridge switchdev: Require RTNL mutex to be held when sending FDB notifications 2016-01-28 16:21:31 -08:00
caif net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA 2015-12-01 15:45:05 -05:00
can can: avoid using timeval for uapi 2015-10-13 17:42:34 +02:00
ceph libceph: remove outdated comment 2016-01-21 19:36:09 +01:00
core gro: Make GRO aware of lightweight tunnels. 2016-01-20 18:48:38 -08:00
dcb net/dcb: make dcbnl.c explicitly non-modular 2015-10-09 07:52:27 -07:00
dccp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-12-03 21:09:12 -05:00
decnet net: add validation for the socket syscall protocol argument 2015-12-14 16:09:30 -05:00
dns_resolver net: dns_resolver: convert time_t to time64_t 2015-11-18 16:27:46 -05:00
dsa dsa: Register netdev before phy 2016-01-07 14:31:26 -05:00
ethernet net: Add eth_platform_get_mac_address() helper. 2016-01-06 16:31:56 -05:00
hsr net/hsr: fix a warning message 2015-11-23 14:56:15 -05:00
ieee802154 inet: kill unused skb_free op 2016-01-05 22:25:57 -05:00
ipv4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-02-01 15:56:08 -08:00
ipv6 ipv6: addrconf: Fix recursive spin lock call 2016-02-06 03:08:15 -05:00
ipx
irda irda: fix a potential use-after-free in ircomm_param_request 2016-01-29 22:56:46 -08:00
iucv af_iucv: Validate socket address length in iucv_sock_bind() 2016-01-19 14:21:08 -05:00
key af_key: fix two typos 2015-10-23 03:05:19 -07:00
l2tp l2tp: rely on ppp layer for skb scrubbing 2016-01-04 16:45:24 -05:00
l3mdev net: Add netif_is_l3_slave 2015-10-07 04:27:43 -07:00
lapb
llc
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-02-01 15:56:08 -08:00
mac802154 mac802154: constify ieee802154_llsec_ops structure 2016-01-04 20:40:41 +01:00
mpls Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-12-17 22:08:28 -05:00
netfilter netfilter: nf_conntrack: use safer way to lock all buckets 2016-01-20 14:15:31 +01:00
netlabel
netlink netlink: not trim skb for mmaped socket when dump 2016-01-29 20:25:17 -08:00
netrom
nfc NFC 4.5 pull request 2016-01-04 21:48:15 -05:00
openvswitch ovs: limit ovs recursions in ovs_execute_actions to not corrupt stack 2016-01-18 12:09:45 -05:00
packet packet: Allow packets with only a header (but no payload) 2015-11-29 22:17:17 -05:00
phonet phonet: properly unshare skbs in phonet_rcv() 2016-01-12 12:05:38 -05:00
rds Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
rfkill rfkill: fix rfkill_fop_read wait_event usage 2016-01-26 11:32:05 +01:00
rose
rxrpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-01-12 18:57:02 -08:00
sched net_sched: drr: check for NULL pointer in drr_dequeue 2016-01-29 17:26:44 -08:00
sctp sctp: remove the dead field of sctp_transport 2016-01-28 15:59:32 -08:00
sunrpc Initial roundup of 4.5 merge window patches 2016-01-23 18:45:06 -08:00
switchdev switchdev: Require RTNL mutex to be held when sending FDB notifications 2016-01-28 16:21:31 -08:00
tipc tipc: fix connection abort during subscription cancel 2016-01-29 15:14:21 -05:00
unix af_unix: fix struct pid memory leak 2016-01-24 22:04:49 -08:00
vmw_vsock Revert "Merge branch 'vsock-virtio'" 2015-12-08 21:55:49 -05:00
wimax
wireless regulatory: fix world regulatory domain data 2016-01-14 11:10:13 +01:00
x25
xfrm net: preserve IP control block during GSO segmentation 2016-01-15 14:35:24 -05:00
compat.c
Kconfig net, sched: add clsact qdisc 2016-01-10 22:13:15 -05:00
Makefile net: Introduce L3 Master device abstraction 2015-09-29 20:40:32 -07:00
socket.c kmemcg: account certain kmem allocations to memcg 2016-01-14 16:00:49 -08:00
sysctl_net.c net: sysctl: fix a kmemleak warning 2015-10-23 06:22:08 -07:00