| Message ID | 20190131131507.GA19807@kroah.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915: do not return invalid pointers as a *dentry | expand |
On Thu, Jan 31, 2019 at 02:15:07PM +0100, Greg Kroah-Hartman wrote: > When calling debugfs functions, they can now return error values if > something went wrong. If that happens, return a NULL as a *dentry to > the relay core instead of passing it an illegal pointer. > > The relay core should be able to handle an illegal pointer, but add this > check to be safe. > > Cc: Jani Nikula <jani.nikula@linux.intel.com> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> > Cc: David Airlie <airlied@linux.ie> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: intel-gfx@lists.freedesktop.org > Cc: dri-devel@lists.freedesktop.org > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > --- > drivers/gpu/drm/i915/intel_guc_log.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_guc_log.c b/drivers/gpu/drm/i915/intel_guc_log.c > index d3ebdbc0182e..8bf03497dcd8 100644 > --- a/drivers/gpu/drm/i915/intel_guc_log.c > +++ b/drivers/gpu/drm/i915/intel_guc_log.c > @@ -140,6 +140,9 @@ static struct dentry *create_buf_file_callback(const char *filename, > > buf_file = debugfs_create_file(filename, mode, > parent, buf, &relay_file_operations); > + if (IS_ERR(buf_file)) > + return NULL; I still see a return NULL inside debugfs_create_file on master, but probably you are ahead with some change that I didn't see yet right? I'm just wondering if it wouldn't be better for now to go with if (IS_ERR_OR_NULL(buf_file)) apparently we also need it on i915_debugfs.c i915_debugfs_register() Thanks, Rodrigo. > + > return buf_file; > } > > -- > 2.20.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On Thu, Jan 31, 2019 at 09:59:26AM -0800, Rodrigo Vivi wrote: > On Thu, Jan 31, 2019 at 02:15:07PM +0100, Greg Kroah-Hartman wrote: > > When calling debugfs functions, they can now return error values if > > something went wrong. If that happens, return a NULL as a *dentry to > > the relay core instead of passing it an illegal pointer. > > > > The relay core should be able to handle an illegal pointer, but add this > > check to be safe. > > > > Cc: Jani Nikula <jani.nikula@linux.intel.com> > > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> > > Cc: David Airlie <airlied@linux.ie> > > Cc: Daniel Vetter <daniel@ffwll.ch> > > Cc: intel-gfx@lists.freedesktop.org > > Cc: dri-devel@lists.freedesktop.org > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > --- > > drivers/gpu/drm/i915/intel_guc_log.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/intel_guc_log.c b/drivers/gpu/drm/i915/intel_guc_log.c > > index d3ebdbc0182e..8bf03497dcd8 100644 > > --- a/drivers/gpu/drm/i915/intel_guc_log.c > > +++ b/drivers/gpu/drm/i915/intel_guc_log.c > > @@ -140,6 +140,9 @@ static struct dentry *create_buf_file_callback(const char *filename, > > > > buf_file = debugfs_create_file(filename, mode, > > parent, buf, &relay_file_operations); > > + if (IS_ERR(buf_file)) > > + return NULL; > > I still see a return NULL inside debugfs_create_file on master, > but probably you are ahead with some change that I didn't see yet right? Yes, this patch is in linux-next now and should go to Linus for 5.0-final: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/commit/?h=driver-core-linus&id=ff9fb72bc07705c00795ca48631f7fffe24d2c6b > I'm just wondering if it wouldn't be better for now to go with > > if (IS_ERR_OR_NULL(buf_file)) Not really, because the next line is: > > return buf_file; So it's the same thing :) > apparently we also need it on i915_debugfs.c i915_debugfs_register() I have a bunch of patches I'm working on to go through and fix up all of this (you shouldn't be checking the return value at all, unless you really want to use it as a "real" dentry and not just something that debugfs uses internally. But for now, you should be fine, that call will only fail if you are out of memory, or did something really wrong. thanks, greg k-h
On Thu, Jan 31, 2019 at 07:17:02PM +0100, Greg Kroah-Hartman wrote: > On Thu, Jan 31, 2019 at 09:59:26AM -0800, Rodrigo Vivi wrote: > > On Thu, Jan 31, 2019 at 02:15:07PM +0100, Greg Kroah-Hartman wrote: > > > When calling debugfs functions, they can now return error values if > > > something went wrong. If that happens, return a NULL as a *dentry to > > > the relay core instead of passing it an illegal pointer. > > > > > > The relay core should be able to handle an illegal pointer, but add this > > > check to be safe. > > > > > > Cc: Jani Nikula <jani.nikula@linux.intel.com> > > > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > > > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> > > > Cc: David Airlie <airlied@linux.ie> > > > Cc: Daniel Vetter <daniel@ffwll.ch> > > > Cc: intel-gfx@lists.freedesktop.org > > > Cc: dri-devel@lists.freedesktop.org > > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > > --- > > > drivers/gpu/drm/i915/intel_guc_log.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/i915/intel_guc_log.c b/drivers/gpu/drm/i915/intel_guc_log.c > > > index d3ebdbc0182e..8bf03497dcd8 100644 > > > --- a/drivers/gpu/drm/i915/intel_guc_log.c > > > +++ b/drivers/gpu/drm/i915/intel_guc_log.c > > > @@ -140,6 +140,9 @@ static struct dentry *create_buf_file_callback(const char *filename, > > > > > > buf_file = debugfs_create_file(filename, mode, > > > parent, buf, &relay_file_operations); > > > + if (IS_ERR(buf_file)) > > > + return NULL; > > > > I still see a return NULL inside debugfs_create_file on master, > > but probably you are ahead with some change that I didn't see yet right? > > Yes, this patch is in linux-next now and should go to Linus for > 5.0-final: > https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/commit/?h=driver-core-linus&id=ff9fb72bc07705c00795ca48631f7fffe24d2c6b > > > I'm just wondering if it wouldn't be better for now to go with > > > > if (IS_ERR_OR_NULL(buf_file)) > > Not really, because the next line is: > > > > return buf_file; > > So it's the same thing :) > > > apparently we also need it on i915_debugfs.c i915_debugfs_register() > > I have a bunch of patches I'm working on to go through and fix up all of > this (you shouldn't be checking the return value at all, unless you > really want to use it as a "real" dentry and not just something that > debugfs uses internally. > > But for now, you should be fine, that call will only fail if you are out > of memory, or did something really wrong. Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> do you wanna push this with your own stuff or do you want me to pick up on drm-intel-next? > > thanks, > > greg k-h > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On Mon, Feb 04, 2019 at 10:13:25AM -0800, Rodrigo Vivi wrote: > On Thu, Jan 31, 2019 at 07:17:02PM +0100, Greg Kroah-Hartman wrote: > > On Thu, Jan 31, 2019 at 09:59:26AM -0800, Rodrigo Vivi wrote: > > > On Thu, Jan 31, 2019 at 02:15:07PM +0100, Greg Kroah-Hartman wrote: > > > > When calling debugfs functions, they can now return error values if > > > > something went wrong. If that happens, return a NULL as a *dentry to > > > > the relay core instead of passing it an illegal pointer. > > > > > > > > The relay core should be able to handle an illegal pointer, but add this > > > > check to be safe. > > > > > > > > Cc: Jani Nikula <jani.nikula@linux.intel.com> > > > > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > > > > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> > > > > Cc: David Airlie <airlied@linux.ie> > > > > Cc: Daniel Vetter <daniel@ffwll.ch> > > > > Cc: intel-gfx@lists.freedesktop.org > > > > Cc: dri-devel@lists.freedesktop.org > > > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > > > --- > > > > drivers/gpu/drm/i915/intel_guc_log.c | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > > > diff --git a/drivers/gpu/drm/i915/intel_guc_log.c b/drivers/gpu/drm/i915/intel_guc_log.c > > > > index d3ebdbc0182e..8bf03497dcd8 100644 > > > > --- a/drivers/gpu/drm/i915/intel_guc_log.c > > > > +++ b/drivers/gpu/drm/i915/intel_guc_log.c > > > > @@ -140,6 +140,9 @@ static struct dentry *create_buf_file_callback(const char *filename, > > > > > > > > buf_file = debugfs_create_file(filename, mode, > > > > parent, buf, &relay_file_operations); > > > > + if (IS_ERR(buf_file)) > > > > + return NULL; > > > > > > I still see a return NULL inside debugfs_create_file on master, > > > but probably you are ahead with some change that I didn't see yet right? > > > > Yes, this patch is in linux-next now and should go to Linus for > > 5.0-final: > > https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/commit/?h=driver-core-linus&id=ff9fb72bc07705c00795ca48631f7fffe24d2c6b > > > > > I'm just wondering if it wouldn't be better for now to go with > > > > > > if (IS_ERR_OR_NULL(buf_file)) > > > > Not really, because the next line is: > > > > > > return buf_file; > > > > So it's the same thing :) > > > > > apparently we also need it on i915_debugfs.c i915_debugfs_register() > > > > I have a bunch of patches I'm working on to go through and fix up all of > > this (you shouldn't be checking the return value at all, unless you > > really want to use it as a "real" dentry and not just something that > > debugfs uses internally. > > > > But for now, you should be fine, that call will only fail if you are out > > of memory, or did something really wrong. > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> > > do you wanna push this with your own stuff or do you want me to pick > up on drm-intel-next? Which ever is easiest for you works for me, just let me know. thanks, greg k-h
On Mon, Feb 04, 2019 at 08:37:01PM +0100, Greg Kroah-Hartman wrote: > On Mon, Feb 04, 2019 at 10:13:25AM -0800, Rodrigo Vivi wrote: > > On Thu, Jan 31, 2019 at 07:17:02PM +0100, Greg Kroah-Hartman wrote: > > > On Thu, Jan 31, 2019 at 09:59:26AM -0800, Rodrigo Vivi wrote: > > > > On Thu, Jan 31, 2019 at 02:15:07PM +0100, Greg Kroah-Hartman wrote: > > > > > When calling debugfs functions, they can now return error values if > > > > > something went wrong. If that happens, return a NULL as a *dentry to > > > > > the relay core instead of passing it an illegal pointer. > > > > > > > > > > The relay core should be able to handle an illegal pointer, but add this > > > > > check to be safe. > > > > > > > > > > Cc: Jani Nikula <jani.nikula@linux.intel.com> > > > > > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > > > > > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> > > > > > Cc: David Airlie <airlied@linux.ie> > > > > > Cc: Daniel Vetter <daniel@ffwll.ch> > > > > > Cc: intel-gfx@lists.freedesktop.org > > > > > Cc: dri-devel@lists.freedesktop.org > > > > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > > > > --- > > > > > drivers/gpu/drm/i915/intel_guc_log.c | 3 +++ > > > > > 1 file changed, 3 insertions(+) > > > > > > > > > > diff --git a/drivers/gpu/drm/i915/intel_guc_log.c b/drivers/gpu/drm/i915/intel_guc_log.c > > > > > index d3ebdbc0182e..8bf03497dcd8 100644 > > > > > --- a/drivers/gpu/drm/i915/intel_guc_log.c > > > > > +++ b/drivers/gpu/drm/i915/intel_guc_log.c > > > > > @@ -140,6 +140,9 @@ static struct dentry *create_buf_file_callback(const char *filename, > > > > > > > > > > buf_file = debugfs_create_file(filename, mode, > > > > > parent, buf, &relay_file_operations); > > > > > + if (IS_ERR(buf_file)) > > > > > + return NULL; > > > > > > > > I still see a return NULL inside debugfs_create_file on master, > > > > but probably you are ahead with some change that I didn't see yet right? > > > > > > Yes, this patch is in linux-next now and should go to Linus for > > > 5.0-final: > > > https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/commit/?h=driver-core-linus&id=ff9fb72bc07705c00795ca48631f7fffe24d2c6b > > > > > > > I'm just wondering if it wouldn't be better for now to go with > > > > > > > > if (IS_ERR_OR_NULL(buf_file)) > > > > > > Not really, because the next line is: > > > > > > > > return buf_file; > > > > > > So it's the same thing :) > > > > > > > apparently we also need it on i915_debugfs.c i915_debugfs_register() > > > > > > I have a bunch of patches I'm working on to go through and fix up all of > > > this (you shouldn't be checking the return value at all, unless you > > > really want to use it as a "real" dentry and not just something that > > > debugfs uses internally. > > > > > > But for now, you should be fine, that call will only fail if you are out > > > of memory, or did something really wrong. > > > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> > > > > do you wanna push this with your own stuff or do you want me to pick > > up on drm-intel-next? > > Which ever is easiest for you works for me, just let me know. pushed to dinq... will be on 5.1 Thanks, Rodrigo. > > thanks, > > greg k-h > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff --git a/drivers/gpu/drm/i915/intel_guc_log.c b/drivers/gpu/drm/i915/intel_guc_log.c index d3ebdbc0182e..8bf03497dcd8 100644 --- a/drivers/gpu/drm/i915/intel_guc_log.c +++ b/drivers/gpu/drm/i915/intel_guc_log.c @@ -140,6 +140,9 @@ static struct dentry *create_buf_file_callback(const char *filename, buf_file = debugfs_create_file(filename, mode, parent, buf, &relay_file_operations); + if (IS_ERR(buf_file)) + return NULL; + return buf_file; }
When calling debugfs functions, they can now return error values if something went wrong. If that happens, return a NULL as a *dentry to the relay core instead of passing it an illegal pointer. The relay core should be able to handle an illegal pointer, but add this check to be safe. Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/gpu/drm/i915/intel_guc_log.c | 3 +++ 1 file changed, 3 insertions(+)