From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net: filter: initialize A and X registers
Date: Tue, 22 Apr 2014 23:57:45 -0400 (EDT)
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From: Alexei Starovoitov <ast@plumgrid.com>
Date: Tue, 22 Apr 2014 20:18:57 -0700

> exisiting BPF verifier allows uninitialized access to registers,
> 'ret A' is considered to be a valid filter.
> So initialize A and X to zero to prevent leaking kernel memory
> In the future BPF verifier will be rejecting such filters
> 
> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>

Has the code always been like this?

Did the eBPF changes introduce this problem either directly or
indirectly?