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Date:   Wed, 01 Aug 2018 11:46:36 -0700 (PDT)
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Subject: Re: KASAN: use-after-free Read in rtnetlink_put_metrics
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From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Tue, 31 Jul 2018 16:03:13 -0700

> Looks like this commit is completely unnecessary,
> fib6_drop_pcpu_from() calls fib6_info_release()
> which calls fib6_info_destroy_rcu(), so this metrics
> will be released twice...

And even if there was a leak here, it's illegal to free this
metrics memory synchronously since it is RCU protected.

That's why it normally goes through fib6_info_destroy_rcu().

Sabrina, I'm going to revert your changes unless I see some
progress here by the end of today.