diff mbox series

staging: media: atomisp: Use kvfree_sensitive in a few places

Message ID 20200909195403.225084-1-alex.dewar90@gmail.com
State New
Headers show
Series staging: media: atomisp: Use kvfree_sensitive in a few places | expand

Commit Message

Alex Dewar Sept. 9, 2020, 7:53 p.m. UTC
In the file pci/sh_css_params.c, there are a number of places where
memset+kvfree is used, where kvfree_sensitive could be used instead. Fix
these occurrences.

Issue identified with Coccinelle.

Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
---
 .../staging/media/atomisp/pci/sh_css_params.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

Comments

Dan Carpenter Sept. 9, 2020, 8:06 p.m. UTC | #1
On Wed, Sep 09, 2020 at 08:53:50PM +0100, Alex Dewar wrote:
> In the file pci/sh_css_params.c, there are a number of places where
> memset+kvfree is used, where kvfree_sensitive could be used instead. Fix
> these occurrences.

This doesn't say *why* the commit is doing it.  There are two reasons:
The worry with these is that the compiler could optimize away the memset
because it sees the kfree().  Second using kvfree_sensitive() is more
clear and readable.

> 
> Issue identified with Coccinelle.
> 
> Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> ---
>  .../staging/media/atomisp/pci/sh_css_params.c | 19 +++++++------------
>  1 file changed, 7 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/staging/media/atomisp/pci/sh_css_params.c b/drivers/staging/media/atomisp/pci/sh_css_params.c
> index 2c67c23b3700..d1b5d6608d52 100644
> --- a/drivers/staging/media/atomisp/pci/sh_css_params.c
> +++ b/drivers/staging/media/atomisp/pci/sh_css_params.c
> @@ -4378,8 +4378,7 @@ ia_css_3a_statistics_free(struct ia_css_3a_statistics *me)
>  	if (me) {
>  		kvfree(me->rgby_data);
>  		kvfree(me->data);
> -		memset(me, 0, sizeof(struct ia_css_3a_statistics));
> -		kvfree(me);
> +		kvfree_sensitive(me, sizeof(struct ia_css_3a_statistics));

I don't think ia_css_3a_statistics are sensitive at all.  What we're
trying to protect are things like passwords.  Just delete the memset.

Looking below, I don't think any of these are sensitive so just delete
all the memsets.

regards,
dan carpenter
diff mbox series

Patch

diff --git a/drivers/staging/media/atomisp/pci/sh_css_params.c b/drivers/staging/media/atomisp/pci/sh_css_params.c
index 2c67c23b3700..d1b5d6608d52 100644
--- a/drivers/staging/media/atomisp/pci/sh_css_params.c
+++ b/drivers/staging/media/atomisp/pci/sh_css_params.c
@@ -4378,8 +4378,7 @@  ia_css_3a_statistics_free(struct ia_css_3a_statistics *me)
 	if (me) {
 		kvfree(me->rgby_data);
 		kvfree(me->data);
-		memset(me, 0, sizeof(struct ia_css_3a_statistics));
-		kvfree(me);
+		kvfree_sensitive(me, sizeof(struct ia_css_3a_statistics));
 	}
 }
 
@@ -4417,8 +4416,7 @@  ia_css_dvs_statistics_free(struct ia_css_dvs_statistics *me)
 	if (me) {
 		kvfree(me->hor_proj);
 		kvfree(me->ver_proj);
-		memset(me, 0, sizeof(struct ia_css_dvs_statistics));
-		kvfree(me);
+		kvfree_sensitive(me, sizeof(struct ia_css_dvs_statistics));
 	}
 }
 
@@ -4459,8 +4457,7 @@  ia_css_dvs_coefficients_free(struct ia_css_dvs_coefficients *me)
 	if (me) {
 		kvfree(me->hor_coefs);
 		kvfree(me->ver_coefs);
-		memset(me, 0, sizeof(struct ia_css_dvs_coefficients));
-		kvfree(me);
+		kvfree_sensitive(me, sizeof(struct ia_css_dvs_coefficients));
 	}
 }
 
@@ -4551,8 +4548,7 @@  ia_css_dvs2_statistics_free(struct ia_css_dvs2_statistics *me)
 		kvfree(me->ver_prod.odd_imag);
 		kvfree(me->ver_prod.even_real);
 		kvfree(me->ver_prod.even_imag);
-		memset(me, 0, sizeof(struct ia_css_dvs2_statistics));
-		kvfree(me);
+		kvfree_sensitive(me, sizeof(struct ia_css_dvs2_statistics));
 	}
 }
 
@@ -4635,8 +4631,7 @@  ia_css_dvs2_coefficients_free(struct ia_css_dvs2_coefficients *me)
 		kvfree(me->ver_coefs.odd_imag);
 		kvfree(me->ver_coefs.even_real);
 		kvfree(me->ver_coefs.even_imag);
-		memset(me, 0, sizeof(struct ia_css_dvs2_coefficients));
-		kvfree(me);
+		kvfree_sensitive(me, sizeof(struct ia_css_dvs2_coefficients));
 	}
 }
 
@@ -4710,8 +4705,8 @@  ia_css_dvs2_6axis_config_free(struct ia_css_dvs_6axis_config *dvs_6axis_config)
 		kvfree(dvs_6axis_config->ycoords_y);
 		kvfree(dvs_6axis_config->xcoords_uv);
 		kvfree(dvs_6axis_config->ycoords_uv);
-		memset(dvs_6axis_config, 0, sizeof(struct ia_css_dvs_6axis_config));
-		kvfree(dvs_6axis_config);
+		kvfree_sensitive(dvs_6axis_config,
+				 sizeof(struct ia_css_dvs_6axis_config));
 	}
 }