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 for <linuxppc-dev@lists.ozlabs.org>; Fri, 16 Oct 2015 17:20:17 +1100 (AEDT)
Subject: Re: [PATCH v2] powerpc/mpc5xxx: Avoid dereferencing potentially freed
 memory
To: Michael Ellerman <mpe@ellerman.id.au>
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From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
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Date: Fri, 16 Oct 2015 08:20:13 +0200
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Le 15/10/2015 08:36, Michael Ellerman a écrit :
> On Thu, 2015-10-15 at 07:56 +0200, Christophe JAILLET wrote:
>> Use 'of_property_read_u32()' instead of 'of_get_property()'+pointer
>> dereference in order to avoid access to potentially freed memory.
>>
>> Use 'of_get_next_parent()' to simplify the while() loop and avoid the
>> need of a temp variable.
>>
>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>> ---
>> v2: Use of_property_read_u32 instead of of_get_property+pointer dereference
>> *** Untested ***
> Thanks.
>
> Can someone with an mpc5xxx test this?
>
> cheers
>

Hi,
I don't think it is an issue, but while looking at another similar 
patch, I noticed that the proposed patch adds a call to be32_to_cpup() 
(within of_property_read_u32).
Apparently, powerPC is a BE architecture, so this call should be a no-op.

Just wanted to point it out, in case of.

Best regards,
CJ