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From: Rabin Vincent <rabin@rab.in>
Subject: Re: [PATCH] arm64: net: bpf: don't BUG() on large shifts
Date: Wed, 6 Jan 2016 21:31:27 +0100
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To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
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On Tue, Jan 05, 2016 at 09:55:58AM -0800, Alexei Starovoitov wrote:
> this one is better to be addressed in verifier instead of eBPF JITs.
> Please reject it in check_alu_op() instead.

AFAICS the eBPF verifier is not called on the eBPF filters generated by
the BPF->eBPF conversion in net/core/filter.c, so performing this check
only in check_alu_op() will be insufficient.  So I think we'd need to
add this check to bpf_check_classic() too.  Or am I missing something?