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Subject: Re: [PATCH] evh_bytechan: fix out of bounds accesses
To: Stephen Rothwell <sfr@canb.auug.org.au>
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From: Timur Tabi <timur@kernel.org>
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Date: Mon, 13 Jan 2020 19:10:11 -0600
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On 1/13/20 2:25 PM, Stephen Rothwell wrote:
> The problem is not really the declaration, the problem is that
> ev_byte_channel_send always accesses 16 bytes from the buffer and it is
> not always passed a buffer that long (in one case it is passed a
> pointer to a single byte).  So the alternative to the memcpy approach I
> have take is to complicate ev_byte_channel_send so that only accesses
> count bytes from the buffer.

Ah, I see now.  This is all coming back to me.

I would prefer that ev_byte_channel_send() is updated to access only 
'count' bytes.  If that means adding a memcpy to the 
ev_byte_channel_send() itself, then so be it.  Trying to figure out how 
to stuff n bytes into 4 32-bit registers is probably not worth the effort.