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Date: Mon, 19 Feb 2024 08:45:54 +0300
From: Dan Carpenter <dan.carpenter@linaro.org>
To: "Cabiddu, Giovanni" <giovanni.cabiddu@intel.com>
Cc: Damian Muszynski <damian.muszynski@intel.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>,
	Lucas Segarra Fernandez <lucas.segarra.fernandez@intel.com>,
	Tero Kristo <tero.kristo@linux.intel.com>,
	Markas Rapoportas <markas.rapoportas@intel.com>,
	qat-linux@intel.com, linux-crypto@vger.kernel.org,
	linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] crypto: qat - uninitialized variable in
 adf_hb_error_inject_write()
Message-ID: <42ad3d09-649c-4dc1-84e4-7aacd3f97ce0@moroto.mountain>
References: <193d36b0-961a-4b66-b945-37988f157ebe@moroto.mountain>
 <Zc+Z7RBFNLcnzNOL@gcabiddu-mobl.ger.corp.intel.com>
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In-Reply-To: <Zc+Z7RBFNLcnzNOL@gcabiddu-mobl.ger.corp.intel.com>

On Fri, Feb 16, 2024 at 05:22:53PM +0000, Cabiddu, Giovanni wrote:
> > --- a/drivers/crypto/intel/qat/qat_common/adf_heartbeat_dbgfs.c
> > +++ b/drivers/crypto/intel/qat/qat_common/adf_heartbeat_dbgfs.c
> > @@ -160,16 +160,17 @@ static ssize_t adf_hb_error_inject_write(struct file *file,
> >  					 size_t count, loff_t *ppos)
> >  {
> >  	struct adf_accel_dev *accel_dev = file->private_data;
> > -	size_t written_chars;
> >  	char buf[3];
> >  	int ret;
> >  
> >  	/* last byte left as string termination */
> > -	if (count != 2)
> > +	if (*ppos != 0 || count != 2)
> Is this alone not sufficient to fix the problem? Probably I'm missing
> something.
> The function just checks the first character in buf.

I mean, technically, yes.

But leaving the last character uninitialized is ugly...  Using
simple_write_to_buffer() was inappropriate because it's not like this
code supported partial writes.  Better to just fix it all the way so no
one copy and pastes it somewhere else.

> 
> Anyway, looks correct to me.
> Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>

Thanks!

regards,
dan carpenter