[patch] fsl/fman: fix a leak in tgec_free()

[patch] fsl/fman: fix a leak in tgec_free()

[Dan Carpenter]

We set "tgec->cfg" to NULL before passing it to kfree().  There is no
need to set it to NULL at all.  Let's just delete it.

Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
I haven't tested this.  It occurs to me that this code might be
something to paper over a use after free bug by changing it to a leak
instead.

It applies to net-master.

diff --git a/drivers/net/ethernet/freescale/fman/fman_tgec.c b/drivers/net/ethernet/freescale/fman/fman_tgec.c
index efabb04..4b0f3a5 100644
--- a/drivers/net/ethernet/freescale/fman/fman_tgec.c
+++ b/drivers/net/ethernet/freescale/fman/fman_tgec.c
@@ -722,9 +722,6 @@ int tgec_free(struct fman_mac *tgec)
 {
 	free_init_resources(tgec);
 
-	if (tgec->cfg)
-		tgec->cfg = NULL;
-
 	kfree(tgec->cfg);
 	kfree(tgec);
 

[patch] fsl/fman: fix a leak in tgec_free()

[Dan Carpenter]

We set "tgec->cfg" to NULL before passing it to kfree().  There is no
need to set it to NULL at all.  Let's just delete it.

Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
I haven't tested this.  It occurs to me that this code might be
something to paper over a use after free bug by changing it to a leak
instead.

It applies to net-master.

diff --git a/drivers/net/ethernet/freescale/fman/fman_tgec.c b/drivers/net/ethernet/freescale/fman/fman_tgec.c
index efabb04..4b0f3a5 100644
--- a/drivers/net/ethernet/freescale/fman/fman_tgec.c
+++ b/drivers/net/ethernet/freescale/fman/fman_tgec.c
@@ -722,9 +722,6 @@ int tgec_free(struct fman_mac *tgec)
 {
 	free_init_resources(tgec);
 
-	if (tgec->cfg)
-		tgec->cfg = NULL;
-
 	kfree(tgec->cfg);
 	kfree(tgec);
 

RE: [patch] fsl/fman: fix a leak in tgec_free()

[Madalin-Cristian Bucur]

> -----Original Message-----
> From: Dan Carpenter [mailto:dan.carpenter@oracle.com]
> Sent: Thursday, November 24, 2016 1:21 PM
> To: Madalin-Cristian Bucur <madalin.bucur@nxp.com>; Igal Liberman
> <igal.liberman@freescale.com>
> Cc: netdev@vger.kernel.org; kernel-janitors@vger.kernel.org
> Subject: [patch] fsl/fman: fix a leak in tgec_free()
> 
> We set "tgec->cfg" to NULL before passing it to kfree().  There is no
> need to set it to NULL at all.  Let's just delete it.

Agree, thanks.

 
> Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> I haven't tested this.  It occurs to me that this code might be
> something to paper over a use after free bug by changing it to a leak
> instead.
> 
> It applies to net-master.
> 
> diff --git a/drivers/net/ethernet/freescale/fman/fman_tgec.c
> b/drivers/net/ethernet/freescale/fman/fman_tgec.c
> index efabb04..4b0f3a5 100644
> --- a/drivers/net/ethernet/freescale/fman/fman_tgec.c
> +++ b/drivers/net/ethernet/freescale/fman/fman_tgec.c
> @@ -722,9 +722,6 @@ int tgec_free(struct fman_mac *tgec)
>  {
>  	free_init_resources(tgec);
> 
> -	if (tgec->cfg)
> -		tgec->cfg = NULL;
> -
>  	kfree(tgec->cfg);
>  	kfree(tgec);
> 

Re: [patch] fsl/fman: fix a leak in tgec_free()

[David Miller]

From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 24 Nov 2016 14:20:43 +0300

> We set "tgec->cfg" to NULL before passing it to kfree().  There is no
> need to set it to NULL at all.  Let's just delete it.
> 
> Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Applied.

Re: [patch] fsl/fman: fix a leak in tgec_free()

[David Miller]

From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 24 Nov 2016 14:20:43 +0300

> We set "tgec->cfg" to NULL before passing it to kfree().  There is no
> need to set it to NULL at all.  Let's just delete it.
> 
> Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Applied.