2013-08-12 08:19:19

by Berg, Johannes

Subject: RE: [PATCH] iwlwifi: mvm: make debugfs write() operations write up to count bytes

> Some debugfs write() operations of the MVM Firmware will ignore the count
> argument, and will copy more bytes than what was specified.
> Fix this by getting the right count of bytes.
>
> This will also honor restrictions put on the number of bytes to write.

That makes some sense.

> To be consitant this patch also switches the initializer from 'char buf[x] = {}' to
> the explicit memset() as it is done in other places of the same file.

I'd rather this (a) be done in a separate patch, and (b) the other way around, switch everything to C99.

> Cc: [email protected]

That doesn't really make sense for the debugfs interface.

> + memset(buf, 0, sizeof(buf));
> + if (count > sizeof(buf) - 1)
> + count = sizeof(buf) - 1;

Why -1? And why not use min()/min_t()?

johannes
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2013-08-12 12:40:07

by Djalal Harouni

Subject: Re: [PATCH] iwlwifi: mvm: make debugfs write() operations write up to count bytes

On Mon, Aug 12, 2013 at 08:19:12AM +0000, Berg, Johannes wrote:
> > Some debugfs write() operations of the MVM Firmware will ignore the count
> > argument, and will copy more bytes than what was specified.
> > Fix this by getting the right count of bytes.
> >
> > This will also honor restrictions put on the number of bytes to write.
>
> That makes some sense.
And avoid strncmp() on garbage data.

> > To be consitant this patch also switches the initializer from 'char buf[x] = {}' to
> > the explicit memset() as it is done in other places of the same file.
>
> I'd rather this (a) be done in a separate patch, and (b) the other way around, switch everything to C99.
Ok

> > Cc: [email protected]
>
> That doesn't really make sense for the debugfs interface.
Ok

> > + memset(buf, 0, sizeof(buf));
> > + if (count > sizeof(buf) - 1)
> > + count = sizeof(buf) - 1;
>
> Why -1? And why not use min()/min_t()?
Yes -1 to be sure that the processed string is null terminated

Ok will use min_t


Will send a second version, Thanks!

> johannes
> --
>
> Intel GmbH
> Dornacher Strasse 1
> 85622 Feldkirchen/Muenchen, Deutschland
> Sitz der Gesellschaft: Feldkirchen bei Muenchen
> Geschaeftsfuehrer: Christian Lamprechter, Hannes Schwaderer, Douglas Lusk
> Registergericht: Muenchen HRB 47456
> Ust.-IdNr./VAT Registration No.: DE129385895
> Citibank Frankfurt a.M. (BLZ 502 109 00) 600119052
>

--
Djalal Harouni
http://opendz.org