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Date:   Mon, 17 May 2021 08:16:35 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     linux-arch@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
        Christoph Hellwig <hch@lst.de>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Vineet Gupta <vgupta@synopsys.com>,
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Subject: Re: [PATCH 3/6] [v2] hexagon: use generic strncpy/strnlen from_user
Message-ID: <20210517061635.GA23581@lst.de>
References: <20210515101803.924427-1-arnd@kernel.org> <20210515101803.924427-4-arnd@kernel.org>
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On Sat, May 15, 2021 at 12:18:00PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Most per-architecture versions of these functions are broken in some form,
> and they are almost certainly slower than the generic code as well.
> 
> Remove the ones for hexagon and instead use the generic version.
> This custom version reads the data twice for strncpy() by doing an extra
> strnlen(), and it apparently lacks a check for user_addr_max().

I'd be tempted to just remove the first paragraph and reword the second
as:

Remove the hexagon implementation of strncpy/strnlen and instead use the
generic versions.  The hexago version of strncpy reads the data twice by
doing an extra strnlen(), and it apparently lacks a check for
user_addr_max().