LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
* re: can: flexcan: add mcf5441x support
@ 2021-08-03 15:23 Colin Ian King
  2021-08-04  7:20 ` Marc Kleine-Budde
  0 siblings, 1 reply; 2+ messages in thread
From: Colin Ian King @ 2021-08-03 15:23 UTC (permalink / raw)
  To: Angelo Dureghello
  Cc: Wolfgang Grandegger, Marc Kleine-Budde, David S. Miller,
	Jakub Kicinski, linux-can, netdev, linux-kernel

Hi,

Static analysis of linux-next with Coverity has detected a potential
issue with the following commit:

commit d9cead75b1c66b4660b4f87ff339234042d7c6a5
Author: Angelo Dureghello <angelo@kernel-space.org>
Date:   Fri Jul 2 11:48:41 2021 +0200

    can: flexcan: add mcf5441x support

The analysis is as follows:

650 static int flexcan_clks_enable(const struct flexcan_priv *priv)
651 {

   1. var_decl: Declaring variable err without initializer.

652        int err;
653

   2. Condition priv->clk_ipg, taking false branch.

654        if (priv->clk_ipg) {
655                err = clk_prepare_enable(priv->clk_ipg);
656                if (err)
657                        return err;
658        }
659

   3. Condition priv->clk_per, taking false branch.

660        if (priv->clk_per) {
661                err = clk_prepare_enable(priv->clk_per);
662                if (err)
663                        clk_disable_unprepare(priv->clk_ipg);
664        }
665

   Uninitialized scalar variable (UNINIT)
   4. uninit_use: Using uninitialized value err.

666        return err;
667 }

I'm not sure if it's possible for priv->clk_ipg and priv_clk_per to both
be null, so I'm not sure if err can end up being not set. However, it
does seem that either err should be zero or some err value, but I was
unsure how err should be initialized in this corner case. As it stands,
err probably needs to be set just to be safe.

Colin

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: can: flexcan: add mcf5441x support
  2021-08-03 15:23 can: flexcan: add mcf5441x support Colin Ian King
@ 2021-08-04  7:20 ` Marc Kleine-Budde
  0 siblings, 0 replies; 2+ messages in thread
From: Marc Kleine-Budde @ 2021-08-04  7:20 UTC (permalink / raw)
  To: Colin Ian King
  Cc: Angelo Dureghello, Wolfgang Grandegger, David S. Miller,
	Jakub Kicinski, linux-can, netdev, linux-kernel

[-- Attachment #1: Type: text/plain, Size: 890 bytes --]

On 03.08.2021 16:23:26, Colin Ian King wrote:
> I'm not sure if it's possible for priv->clk_ipg and priv_clk_per to both
> be null, so I'm not sure if err can end up being not set. However, it
> does seem that either err should be zero or some err value, but I was
> unsure how err should be initialized in this corner case. As it stands,
> err probably needs to be set just to be safe.

ACK - There was already a patch that fixes the problem, but I've not
included it in a pull request:

https://lore.kernel.org/linux-can/20210728075428.1493568-1-mkl@pengutronix.de/

Will send now one.

regards,
Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde           |
Embedded Linux                   | https://www.pengutronix.de  |
Vertretung West/Dortmund         | Phone: +49-231-2826-924     |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-5555 |

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2021-08-04  7:21 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-03 15:23 can: flexcan: add mcf5441x support Colin Ian King
2021-08-04  7:20 ` Marc Kleine-Budde

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).