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Date:   Mon, 21 Aug 2023 09:03:31 +0200
From:   Simon Horman <horms@kernel.org>
To:     "GONG, Ruiqi" <gongruiqi@huaweicloud.com>
Cc:     Chris Snook <chris.snook@gmail.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Sabrina Dubroca <sd@queasysnail.net>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>,
        "Gustavo A . R . Silva" <gustavoars@kernel.org>,
        gongruiqi1@huawei.com
Subject: Re: [PATCH RESEND net-next] alx: fix OOB-read compiler warning
Message-ID: <20230821070331.GA2711035@kernel.org>
References: <20230821013218.1614265-1-gongruiqi@huaweicloud.com>
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On Mon, Aug 21, 2023 at 09:32:18AM +0800, GONG, Ruiqi wrote:
> From: "GONG, Ruiqi" <gongruiqi1@huawei.com>
> 
> The following message shows up when compiling with W=1:
> 
> In function ‘fortify_memcpy_chk’,
>     inlined from ‘alx_get_ethtool_stats’ at drivers/net/ethernet/atheros/alx/ethtool.c:297:2:
> ./include/linux/fortify-string.h:592:4: error: call to ‘__read_overflow2_field’
> declared with attribute warning: detected read beyond size of field (2nd parameter);
> maybe use struct_group()? [-Werror=attribute-warning]
>   592 |    __read_overflow2_field(q_size_field, size);
>       |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> In order to get alx stats altogether, alx_get_ethtool_stats() reads
> beyond hw->stats.rx_ok. Fix this warning by directly copying hw->stats,
> and refactor the unnecessarily complicated BUILD_BUG_ON btw.
> 
> Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>

Reviewed-by: Simon Horman <horms@kernel.org>