From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net/packet: check length in getsockopt() called with
 PACKET_HDRLEN
Date: Tue, 25 Apr 2017 14:06:04 -0400 (EDT)
Message-ID: <20170425.140604.276789553615920800.davem@davemloft.net>
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From: Alexander Potapenko <glider@google.com>
Date: Tue, 25 Apr 2017 18:51:46 +0200

> In the case getsockopt() is called with PACKET_HDRLEN and optlen < 4
> |val| remains uninitialized and the syscall may behave differently
> depending on its value, and even copy garbage to userspace on certain
> architectures. To fix this we now return -EINVAL if optlen is too small.
> 
> This bug has been detected with KMSAN.
> 
> Signed-off-by: Alexander Potapenko <glider@google.com>

Applied, thanks.