From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tomi Valkeinen <tomi.valkeinen@ti.com>
Date: Tue, 13 Jan 2015 11:19:17 +0000
Subject: Re: [patch] fbdev: off by one test (harmless)
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To: linux-fbdev@vger.kernel.org

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On 29/12/14 23:51, David Ung wrote:
>=20
>>> test is really a no-op.  But it's still off by one and upsets the
>>> static checkers so we may as well correct it.
>>
>> 'idx' should be 0~63, because cea_modes array is defined as
>> 'cea_modes[64]'.
>=20
> According to CEA/EIA-861E, there are 64 defined modes, but idx is valid=
 for 1-64, 0 is reserved hence the check for=20
>=20
>         If (!idx || idx > 63) {
>=20
> Think idx check really should be !idx || idx > 64 if following CEA/EIA-=
861E

In that case there's something funny with the code. The code indexes
'cea_modes' using 'idx', and I _think_ cea_modes is already offset
properly, i.e. there's no entry at 0. But its length is 64, which is not
right, as there's the empty item in the beginning.

So maybe the correct fix is to increase the length of cea_modes to 65,
and change the idx check as you mention above?

 Tomi



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