Eric Dumazet 9653359eb6 tcp/dccp: fix another race at listener dismantle ... [ Upstream commit 7716682cc5 ] Ilya reported following lockdep splat: kernel: ========================= kernel: [ BUG: held lock freed! ] kernel: 4.5.0-rc1-ceph-00026-g5e0a311 #1 Not tainted kernel: ------------------------- kernel: swapper/5/0 is freeing memory ffff880035c9d200-ffff880035c9dbff, with a lock still held there! kernel: (&(&queue->rskq_lock)->rlock){+.-...}, at: [<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0 kernel: 4 locks held by swapper/5/0: kernel: #0: (rcu_read_lock){......}, at: [<ffffffff8169ef6b>] netif_receive_skb_internal+0x4b/0x1f0 kernel: #1: (rcu_read_lock){......}, at: [<ffffffff816e977f>] ip_local_deliver_finish+0x3f/0x380 kernel: #2: (slock-AF_INET){+.-...}, at: [<ffffffff81685ffb>] sk_clone_lock+0x19b/0x440 kernel: #3: (&(&queue->rskq_lock)->rlock){+.-...}, at: [<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0 To properly fix this issue, inet_csk_reqsk_queue_add() needs to return to its callers if the child as been queued into accept queue. We also need to make sure listener is still there before calling sk->sk_data_ready(), by holding a reference on it, since the reference carried by the child can disappear as soon as the child is put on accept queue. Reported-by: Ilya Dryomov <idryomov@gmail.com> Fixes: ebb516af60 ("tcp/dccp: fix race at listener dismantle phase") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2016-03-03 15:07:07 -08:00
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acpi	Merge branch 'acpi-pci'	2015-11-07 01:30:10 +01:00
asm-generic	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
clocksource
crypto	crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path	2016-02-17 12:31:03 -08:00
drm	drm/nouveau: Fix pre-nv50 pageflip events (v4)	2015-12-04 13:49:38 +10:00
dt-bindings	ARM: DT updates for v4.4	2015-11-10 15:06:26 -08:00
keys
kvm	KVM: arm/arm64: arch_timer: Preserve physical dist. active state on LR.active	2015-11-24 18:07:40 +01:00
linux	net:Add sysctl_max_skb_frags	2016-03-03 15:07:05 -08:00
math-emu
media
memory
misc
net	tcp/dccp: fix another race at listener dismantle	2016-03-03 15:07:07 -08:00
pcmcia
ras
rdma	IB/mad: Require CM send method for everything except ClassPortInfo	2015-12-08 12:19:11 -05:00
rxrpc
scsi	Merge branch 'mkp-fixes' into fixes	2015-12-03 09:32:33 -08:00
soc	ARM: SoC driver updates for v4.4	2015-11-10 15:00:03 -08:00
sound	ALSA: rawmidi: Make snd_rawmidi_transmit() race-free	2016-02-17 12:30:58 -08:00
target	target: Fix race for SCF_COMPARE_AND_WRITE_POST checking	2015-11-28 19:33:15 -08:00
trace	Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux	2015-11-11 09:03:01 -08:00
uapi	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-12-17 14:05:22 -08:00
video	gpu: ipu-v3: drop unused dmfc field from client platform data	2015-11-24 11:30:15 +01:00
xen	xen: Add RING_COPY_REQUEST()	2015-12-18 10:00:17 -05:00
Kbuild