Re: [PATCH] tpm: return -ENODEV if np is not set

From	Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] tpm: return -ENODEV if np is not set
Date	2016-11-15 18:40 +0100
Message-ID	<sDPS9-7Wd-5@gated-at.bofh.it> (permalink)
References	<sDLYe-5sD-43@gated-at.bofh.it>
Organization	Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

Show all headers | View raw

On Tue, Nov 15, 2016 at 01:27:22PM +0000, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> device_node np contains a garbage value from the stack and it
> is only set if chip->dev.parent->of_node is not null.  Thus the
> check for a null np won't spot a garbage value of np from the
> stack if chip->dev.parent->of_node is null and if np contains
> an garbage non-null value.
> 
> I believe the correct fix is to return -ENODEV if and only if
> chip->dev.parent->of_node is null.
> 
> Found with static analysis by CoverityScan, CID 1377755
> 
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

/Jarkko

> ---
>  drivers/char/tpm/tpm_of.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c
> index 3af829f..1426590 100644
> --- a/drivers/char/tpm/tpm_of.c
> +++ b/drivers/char/tpm/tpm_of.c
> @@ -31,7 +31,7 @@ int read_log_of(struct tpm_chip *chip)
>  	log = &chip->log;
>  	if (chip->dev.parent->of_node)
>  		np = chip->dev.parent->of_node;
> -	if (!np)
> +	else
>  		return -ENODEV;
>  
>  	sizep = of_get_property(np, "linux,sml-size", NULL);
> -- 
> 2.10.2
>

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

[PATCH] tpm: return -ENODEV if np is not set Colin King <colin.king@canonical.com> - 2016-11-15 14:30 +0100
  Re: [PATCH] tpm: return -ENODEV if np is not set Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2016-11-15 18:40 +0100

csiph-web