From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [patch net-next] net: sched: cls_matchall: fix null pointer
 dereference
Date: Mon, 22 May 2017 14:54:46 -0400 (EDT)
Message-ID: <20170522.145446.597984501091102550.davem@davemloft.net>
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From: Jiri Pirko <jiri@resnulli.us>
Date: Mon, 22 May 2017 16:46:13 +0200

> From: Jiri Pirko <jiri@mellanox.com>
> 
> Since the head is guaranteed by the check above to be null, the call_rcu
> would explode. Remove the previously logically dead code that was made
> logically very much alive and kicking.
> 
> Fixes: 985538eee06f ("net/sched: remove redundant null check on head")
> Signed-off-by: Jiri Pirko <jiri@mellanox.com>

Ouch... that's kinda scary.

This fix is needed in the 'net' tree so that's where I have applied
it.

Thanks.