WANG Cong 763dbf6328 net_sched: move the empty tp check from ->destroy() to ->delete() ... We could have a race condition where in ->classify() path we dereference tp->root and meanwhile a parallel ->destroy() makes it a NULL. Daniel cured this bug in commit d936377414 ("net, sched: respect rcu grace period on cls destruction"). This happens when ->destroy() is called for deleting a filter to check if we are the last one in tp, this tp is still linked and visible at that time. The root cause of this problem is the semantic of ->destroy(), it does two things (for non-force case): 1) check if tp is empty 2) if tp is empty we could really destroy it and its caller, if cares, needs to check its return value to see if it is really destroyed. Therefore we can't unlink tp unless we know it is empty. As suggested by Daniel, we could actually move the test logic to ->delete() so that we can safely unlink tp after ->delete() tells us the last one is just deleted and before ->destroy(). Fixes: 1e052be69d ("net_sched: destroy proto tp when all filters are gone") Cc: Roi Dayan <roid@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>		2017-04-21 13:58:15 -04:00
..
acpi
asm-generic	vmlinux.lds: add missing VMLINUX_SYMBOL macros	2017-04-08 00:47:48 -07:00
clocksource
crypto	Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2017-04-18 09:03:50 -07:00
drm	drm/ttm, drm/vmwgfx: Relax permission checking when opening surfaces	2017-03-30 11:43:39 +02:00
dt-bindings	scripts/spelling.txt: add "overide" pattern and fix typo instances	2017-03-09 17:01:09 -08:00
keys
kvm	KVM: arm64: Ensure LRs are clear when they should be	2017-04-04 14:33:58 +02:00
linux	Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning	2017-04-21 13:22:34 -04:00
math-emu
media
memory
misc
net	net_sched: move the empty tp check from ->destroy() to ->delete()	2017-04-21 13:58:15 -04:00
pcmcia
ras
rdma	IB/core: Restore I/O MMU, s390 and powerpc support	2017-03-24 21:51:16 -04:00
rxrpc
scsi
soc
sound
target	target: Fix ALUA transition state race between multiple initiators	2017-03-30 23:12:40 -07:00
trace	rxrpc: Trace client call connection	2017-04-06 11:10:41 +01:00
uapi	bpf: add napi_id read access to __sk_buff	2017-04-21 13:53:27 -04:00
video	drm/exynos/decon5433: signal frame done interrupt at front porch	2017-03-21 13:17:22 +09:00
xen
Kbuild