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Subject: Re: [PATCH bpf v2 2/2] selftests/bpf: add verifier test for
 PTR_TO_MEM spill
To:     Gilad Reti <gilad.reti@gmail.com>, <bpf@vger.kernel.org>
CC:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>, Shuah Khan <shuah@kernel.org>,
        <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-kselftest@vger.kernel.org>
References: <20210113053810.13518-1-gilad.reti@gmail.com>
 <20210113053810.13518-2-gilad.reti@gmail.com>
From:   Yonghong Song <yhs@fb.com>
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Date:   Wed, 13 Jan 2021 08:05:04 -0800
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On 1/12/21 9:38 PM, Gilad Reti wrote:
> Add a test to check that the verifier is able to recognize spilling of
> PTR_TO_MEM registers, by reserving a ringbuf buffer, forcing the spill
> of a pointer holding the buffer address to the stack, filling it back
> in from the stack and writing to the memory area pointed by it.
> 
> The patch was partially contributed by CyberArk Software, Inc.
> 
> Signed-off-by: Gilad Reti <gilad.reti@gmail.com>

I didn't verify result_unpriv = ACCEPT part. I think it is correct
by checking code.

Acked-by: Yonghong Song <yhs@fb.com>