In the impelementation of v3d_submit_cl_ioctl() there are two memory
leaks. One is when allocation for bin fails, and the other is when bin
initialization fails. If kcalloc fails to allocate memory for bin then
render->base should be put. Also, if v3d_job_init() fails to initialize
bin->base then allocated memory for bin should be released.
Fixes: a783a09ee76d ("drm/v3d: Refactor job management.")
Signed-off-by: Navid Emamdoost <[email protected]>
---
drivers/gpu/drm/v3d/v3d_gem.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
index 5d80507b539b..19c092d75266 100644
--- a/drivers/gpu/drm/v3d/v3d_gem.c
+++ b/drivers/gpu/drm/v3d/v3d_gem.c
@@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
if (args->bcl_start != args->bcl_end) {
bin = kcalloc(1, sizeof(*bin), GFP_KERNEL);
- if (!bin)
+ if (!bin) {
+ v3d_job_put(&render->base);
return -ENOMEM;
+ }
ret = v3d_job_init(v3d, file_priv, &bin->base,
v3d_job_free, args->in_sync_bcl);
if (ret) {
v3d_job_put(&render->base);
+ kfree(bin);
return ret;
}
--
2.17.1
> In the impelementation of v3d_submit_cl_ioctl() there are two memory leaks.
Please avoid another typo also in this change description.
> … If kcalloc fails to allocate memory for bin then
> render->base should be put. Also, if v3d_job_init() fails to initialize
> bin->base then allocated memory for bin should be released.
Will an “imperative mood” be more appropriate for such wordings?
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n151
…
> +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
…
> if (ret) {
> v3d_job_put(&render->base);
> + kfree(bin);
…
Can it be helpful to move the added function call before the other
in this if branch (if you prefer to avoid the addition of a jump target here)?
Regards,
Markus
> …
>> +++ b/drivers/gpu/drm/v3d/v3d_gem.c
>> @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
> …
>> if (ret) {
>> v3d_job_put(&render->base);
>> + kfree(bin);
> …
>
> Can it be helpful to move the added function call before the other
> in this if branch (if you prefer to avoid the addition of a jump target here)?
I got into the mood to take another look at these implementation details.
I suggest then to look at the commit 0d352a3a8a1f26168d09f7073e61bb4b328e3bb9
("drm/v3d: don't leak bin job if v3d_job_init fails." from 2019-09-18)
once more.
With which software versions did you perform your source code analysis?
Regards,
Markus
On Mon, Oct 21, 2019 at 01:52:49PM -0500, Navid Emamdoost wrote:
> In the impelementation of v3d_submit_cl_ioctl() there are two memory
> leaks. One is when allocation for bin fails, and the other is when bin
> initialization fails. If kcalloc fails to allocate memory for bin then
> render->base should be put. Also, if v3d_job_init() fails to initialize
> bin->base then allocated memory for bin should be released.
>
> Fixes: a783a09ee76d ("drm/v3d: Refactor job management.")
> Signed-off-by: Navid Emamdoost <[email protected]>
> ---
> drivers/gpu/drm/v3d/v3d_gem.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> index 5d80507b539b..19c092d75266 100644
> --- a/drivers/gpu/drm/v3d/v3d_gem.c
> +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
>
> if (args->bcl_start != args->bcl_end) {
> bin = kcalloc(1, sizeof(*bin), GFP_KERNEL);
> - if (!bin)
> + if (!bin) {
> + v3d_job_put(&render->base);
The job isn't initialized yet, this doesn't work.
> return -ENOMEM;
> + }
>
> ret = v3d_job_init(v3d, file_priv, &bin->base,
> v3d_job_free, args->in_sync_bcl);
> if (ret) {
> v3d_job_put(&render->base);
v3d_job_put will call kfree, if you chase the callchain long enough (in
v3d_job_free). So no bug here, this would lead to a double kfree and
crash.
-Daniel
> + kfree(bin);
> return ret;
> }
>
> --
> 2.17.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
On Tue, Oct 22, 2019 at 4:36 AM Daniel Vetter <[email protected]> wrote:
>
> On Mon, Oct 21, 2019 at 01:52:49PM -0500, Navid Emamdoost wrote:
> > In the impelementation of v3d_submit_cl_ioctl() there are two memory
> > leaks. One is when allocation for bin fails, and the other is when bin
> > initialization fails. If kcalloc fails to allocate memory for bin then
> > render->base should be put. Also, if v3d_job_init() fails to initialize
> > bin->base then allocated memory for bin should be released.
> >
> > Fixes: a783a09ee76d ("drm/v3d: Refactor job management.")
> > Signed-off-by: Navid Emamdoost <[email protected]>
> > ---
> > drivers/gpu/drm/v3d/v3d_gem.c | 5 ++++-
> > 1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> > index 5d80507b539b..19c092d75266 100644
> > --- a/drivers/gpu/drm/v3d/v3d_gem.c
> > +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> > @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
> >
> > if (args->bcl_start != args->bcl_end) {
> > bin = kcalloc(1, sizeof(*bin), GFP_KERNEL);
> > - if (!bin)
> > + if (!bin) {
> > + v3d_job_put(&render->base);
>
> The job isn't initialized yet, this doesn't work.
Do you mean we have to release render via kfree() here?
>
> > return -ENOMEM;
> > + }
> >
> > ret = v3d_job_init(v3d, file_priv, &bin->base,
> > v3d_job_free, args->in_sync_bcl);
> > if (ret) {
> > v3d_job_put(&render->base);
>
> v3d_job_put will call kfree, if you chase the callchain long enough (in
> v3d_job_free). So no bug here, this would lead to a double kfree and
> crash.
Yes, v3d_job_put() takes care of render,
> -Daniel
>
> > + kfree(bin);
but how about leaking bin?
> > return ret;
> > }
> >
> > --
> > 2.17.1
> >
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
--
Navid.
On Tue, Oct 22, 2019 at 10:53:57PM -0500, Navid Emamdoost wrote:
> On Tue, Oct 22, 2019 at 4:36 AM Daniel Vetter <[email protected]> wrote:
> >
> > On Mon, Oct 21, 2019 at 01:52:49PM -0500, Navid Emamdoost wrote:
> > > In the impelementation of v3d_submit_cl_ioctl() there are two memory
> > > leaks. One is when allocation for bin fails, and the other is when bin
> > > initialization fails. If kcalloc fails to allocate memory for bin then
> > > render->base should be put. Also, if v3d_job_init() fails to initialize
> > > bin->base then allocated memory for bin should be released.
> > >
> > > Fixes: a783a09ee76d ("drm/v3d: Refactor job management.")
> > > Signed-off-by: Navid Emamdoost <[email protected]>
> > > ---
> > > drivers/gpu/drm/v3d/v3d_gem.c | 5 ++++-
> > > 1 file changed, 4 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> > > index 5d80507b539b..19c092d75266 100644
> > > --- a/drivers/gpu/drm/v3d/v3d_gem.c
> > > +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> > > @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
> > >
> > > if (args->bcl_start != args->bcl_end) {
> > > bin = kcalloc(1, sizeof(*bin), GFP_KERNEL);
> > > - if (!bin)
> > > + if (!bin) {
> > > + v3d_job_put(&render->base);
> >
> > The job isn't initialized yet, this doesn't work.
> Do you mean we have to release render via kfree() here?
>
> >
> > > return -ENOMEM;
> > > + }
> > >
> > > ret = v3d_job_init(v3d, file_priv, &bin->base,
> > > v3d_job_free, args->in_sync_bcl);
> > > if (ret) {
> > > v3d_job_put(&render->base);
> >
> > v3d_job_put will call kfree, if you chase the callchain long enough (in
> > v3d_job_free). So no bug here, this would lead to a double kfree and
> > crash.
> Yes, v3d_job_put() takes care of render,
>
> > -Daniel
> >
> > > + kfree(bin);
> but how about leaking bin?
Sorry, I totally missed that this is bin, no render. Patch looks correct
to me.
Reviewed-by: Daniel Vetter <[email protected]>
>
> > > return ret;
> > > }
> > >
> > > --
> > > 2.17.1
> > >
> >
> > --
> > Daniel Vetter
> > Software Engineer, Intel Corporation
> > http://blog.ffwll.ch
>
>
>
> --
> Navid.
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
On Wed, Oct 23, 2019 at 11:16:01AM +0200, Daniel Vetter wrote:
> On Tue, Oct 22, 2019 at 10:53:57PM -0500, Navid Emamdoost wrote:
> > On Tue, Oct 22, 2019 at 4:36 AM Daniel Vetter <[email protected]> wrote:
> > >
> > > On Mon, Oct 21, 2019 at 01:52:49PM -0500, Navid Emamdoost wrote:
> > > > In the impelementation of v3d_submit_cl_ioctl() there are two memory
> > > > leaks. One is when allocation for bin fails, and the other is when bin
> > > > initialization fails. If kcalloc fails to allocate memory for bin then
> > > > render->base should be put. Also, if v3d_job_init() fails to initialize
> > > > bin->base then allocated memory for bin should be released.
> > > >
> > > > Fixes: a783a09ee76d ("drm/v3d: Refactor job management.")
> > > > Signed-off-by: Navid Emamdoost <[email protected]>
> > > > ---
> > > > drivers/gpu/drm/v3d/v3d_gem.c | 5 ++++-
> > > > 1 file changed, 4 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> > > > index 5d80507b539b..19c092d75266 100644
> > > > --- a/drivers/gpu/drm/v3d/v3d_gem.c
> > > > +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> > > > @@ -557,13 +557,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
> > > >
> > > > if (args->bcl_start != args->bcl_end) {
> > > > bin = kcalloc(1, sizeof(*bin), GFP_KERNEL);
> > > > - if (!bin)
> > > > + if (!bin) {
> > > > + v3d_job_put(&render->base);
> > >
> > > The job isn't initialized yet, this doesn't work.
> > Do you mean we have to release render via kfree() here?
> >
> > >
> > > > return -ENOMEM;
> > > > + }
> > > >
> > > > ret = v3d_job_init(v3d, file_priv, &bin->base,
> > > > v3d_job_free, args->in_sync_bcl);
> > > > if (ret) {
> > > > v3d_job_put(&render->base);
> > >
> > > v3d_job_put will call kfree, if you chase the callchain long enough (in
> > > v3d_job_free). So no bug here, this would lead to a double kfree and
> > > crash.
> > Yes, v3d_job_put() takes care of render,
> >
> > > -Daniel
> > >
> > > > + kfree(bin);
> > but how about leaking bin?
>
> Sorry, I totally missed that this is bin, no render. Patch looks correct
> to me.
>
> Reviewed-by: Daniel Vetter <[email protected]>
Double-checked with Eric and applied to drm-misc-fixes.
-Daniel
>
> >
> > > > return ret;
> > > > }
> > > >
> > > > --
> > > > 2.17.1
> > > >
> > >
> > > --
> > > Daniel Vetter
> > > Software Engineer, Intel Corporation
> > > http://blog.ffwll.ch
> >
> >
> >
> > --
> > Navid.
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch