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Subject: Re: [PATCH] bpf: Fix backport of "bpf: restrict unknown scalars of
 mixed signed bounds for unprivileged"
To:     Samuel Mendoza-Jonas <samjonas@amazon.com>, <bpf@vger.kernel.org>
CC:     <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <bsingharora@gmail.com>, Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>
References: <20210419235641.5442-1-samjonas@amazon.com>
From:   Yonghong Song <yhs@fb.com>
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On 4/19/21 4:56 PM, Samuel Mendoza-Jonas wrote:
> The 4.14 backport of 9d7eceede ("bpf: restrict unknown scalars of mixed
> signed bounds for unprivileged") adds the PTR_TO_MAP_VALUE check to the
> wrong location in adjust_ptr_min_max_vals(), most likely because 4.14
> doesn't include the commit that updates the if-statement to a
> switch-statement (aad2eeaf4 "bpf: Simplify ptr_min_max_vals adjustment").
> 
> Move the check to the proper location in adjust_ptr_min_max_vals().
> 
> Fixes: 17efa65350c5a ("bpf: restrict unknown scalars of mixed signed bounds for unprivileged")
> Signed-off-by: Samuel Mendoza-Jonas <samjonas@amazon.com>
> Reviewed-by: Frank van der Linden <fllinden@amazon.com>
> Reviewed-by: Ethan Chen <yishache@amazon.com>

Just to be clear, the patch is for 4.14 stable branch.

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