| Message ID | 20200909195403.225084-1-alex.dewar90@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | staging: media: atomisp: Use kvfree_sensitive in a few places | expand |
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
On 2020-09-09 21:06, Dan Carpenter wrote: > 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. Good point :) > >> 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. This makes sense. I'll send a new patch. Thanks for the feedback! Alex > > regards, > dan carpenter >
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)); } }
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(-)