| Message ID | 1519279759-7803-1-git-send-email-andr2000@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/22/2018 08:09 AM, Oleksandr Andrushchenko wrote: > From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > It is possible that drm_simple_kms_plane_atomic_check called > with no CRTC set, e.g. when user-space application sets CRTC_ID/FB_ID > to 0 before doing any actual drawing. This leads to NULL pointer > dereference because in this case new CRTC state is NULL and must be > checked before accessing. > > Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > > --- > Changes since initial: > - re-worked checks for null CRTC as suggested by Daniel Vetter > --- > drivers/gpu/drm/drm_simple_kms_helper.c | 10 +++------- > 1 file changed, 3 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c > index 9ca8a4a59b74..4a1dbd88b1ec 100644 > --- a/drivers/gpu/drm/drm_simple_kms_helper.c > +++ b/drivers/gpu/drm/drm_simple_kms_helper.c > @@ -121,12 +121,6 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, > pipe = container_of(plane, struct drm_simple_display_pipe, plane); > crtc_state = drm_atomic_get_new_crtc_state(plane_state->state, > &pipe->crtc); > - if (!crtc_state->enable) > - return 0; /* nothing to check when disabling or disabled */ > - > - if (crtc_state->enable) > - drm_mode_get_hv_timing(&crtc_state->mode, > - &clip.x2, &clip.y2); > > ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state, > &clip, > @@ -137,7 +131,9 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, > return ret; > > if (!plane_state->visible) > - return -EINVAL; Daniel, I have put your R-b tag, but I had removed suggested "WARN_ON(crtc_state && crtc_state->enable);" here as it fires each time when crtc_state is not NULL. Please let me know if this is not ok and you want me to remove your R-b tag. > + return 0; > + > + drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2); > > if (!pipe->funcs || !pipe->funcs->check) > return 0; Thank you, Oleksandr
On Thu, Feb 22, 2018 at 08:12:48AM +0200, Oleksandr Andrushchenko wrote: > On 02/22/2018 08:09 AM, Oleksandr Andrushchenko wrote: > > From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > > > It is possible that drm_simple_kms_plane_atomic_check called > > with no CRTC set, e.g. when user-space application sets CRTC_ID/FB_ID > > to 0 before doing any actual drawing. This leads to NULL pointer > > dereference because in this case new CRTC state is NULL and must be > > checked before accessing. > > > > Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > > > > --- > > Changes since initial: > > - re-worked checks for null CRTC as suggested by Daniel Vetter > > --- > > drivers/gpu/drm/drm_simple_kms_helper.c | 10 +++------- > > 1 file changed, 3 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c > > index 9ca8a4a59b74..4a1dbd88b1ec 100644 > > --- a/drivers/gpu/drm/drm_simple_kms_helper.c > > +++ b/drivers/gpu/drm/drm_simple_kms_helper.c > > @@ -121,12 +121,6 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, > > pipe = container_of(plane, struct drm_simple_display_pipe, plane); > > crtc_state = drm_atomic_get_new_crtc_state(plane_state->state, > > &pipe->crtc); > > - if (!crtc_state->enable) > > - return 0; /* nothing to check when disabling or disabled */ > > - > > - if (crtc_state->enable) > > - drm_mode_get_hv_timing(&crtc_state->mode, > > - &clip.x2, &clip.y2); > > ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state, > > &clip, > > @@ -137,7 +131,9 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, > > return ret; > > if (!plane_state->visible) > > - return -EINVAL; > Daniel, I have put your R-b tag, but I had removed suggested > "WARN_ON(crtc_state && crtc_state->enable);" > here as it fires each time when crtc_state is not NULL. > Please let me know if this is not ok and you want me to remove > your R-b tag. I'm a bit confused why that fires, but oh well. Applied, thanks for your patch. -Daniel > > + return 0; > > + > > + drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2); > > if (!pipe->funcs || !pipe->funcs->check) > > return 0; > Thank you, > Oleksandr > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On 02/22/2018 06:11 PM, Daniel Vetter wrote: > On Thu, Feb 22, 2018 at 08:12:48AM +0200, Oleksandr Andrushchenko wrote: >> On 02/22/2018 08:09 AM, Oleksandr Andrushchenko wrote: >>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >>> >>> It is possible that drm_simple_kms_plane_atomic_check called >>> with no CRTC set, e.g. when user-space application sets CRTC_ID/FB_ID >>> to 0 before doing any actual drawing. This leads to NULL pointer >>> dereference because in this case new CRTC state is NULL and must be >>> checked before accessing. >>> >>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >>> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> >>> >>> --- >>> Changes since initial: >>> - re-worked checks for null CRTC as suggested by Daniel Vetter >>> --- >>> drivers/gpu/drm/drm_simple_kms_helper.c | 10 +++------- >>> 1 file changed, 3 insertions(+), 7 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c >>> index 9ca8a4a59b74..4a1dbd88b1ec 100644 >>> --- a/drivers/gpu/drm/drm_simple_kms_helper.c >>> +++ b/drivers/gpu/drm/drm_simple_kms_helper.c >>> @@ -121,12 +121,6 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, >>> pipe = container_of(plane, struct drm_simple_display_pipe, plane); >>> crtc_state = drm_atomic_get_new_crtc_state(plane_state->state, >>> &pipe->crtc); >>> - if (!crtc_state->enable) >>> - return 0; /* nothing to check when disabling or disabled */ >>> - >>> - if (crtc_state->enable) >>> - drm_mode_get_hv_timing(&crtc_state->mode, >>> - &clip.x2, &clip.y2); >>> ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state, >>> &clip, >>> @@ -137,7 +131,9 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, >>> return ret; >>> if (!plane_state->visible) >>> - return -EINVAL; >> Daniel, I have put your R-b tag, but I had removed suggested >> "WARN_ON(crtc_state && crtc_state->enable);" >> here as it fires each time when crtc_state is not NULL. >> Please let me know if this is not ok and you want me to remove >> your R-b tag. > I'm a bit confused why that fires, but oh well. Applied, thanks for your > patch. Thank you > -Daniel > >>> + return 0; >>> + >>> + drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2); >>> if (!pipe->funcs || !pipe->funcs->check) >>> return 0; >> Thank you, >> Oleksandr >> _______________________________________________ >> dri-devel mailing list >> dri-devel@lists.freedesktop.org >> https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c index 9ca8a4a59b74..4a1dbd88b1ec 100644 --- a/drivers/gpu/drm/drm_simple_kms_helper.c +++ b/drivers/gpu/drm/drm_simple_kms_helper.c @@ -121,12 +121,6 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, pipe = container_of(plane, struct drm_simple_display_pipe, plane); crtc_state = drm_atomic_get_new_crtc_state(plane_state->state, &pipe->crtc); - if (!crtc_state->enable) - return 0; /* nothing to check when disabling or disabled */ - - if (crtc_state->enable) - drm_mode_get_hv_timing(&crtc_state->mode, - &clip.x2, &clip.y2); ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state, &clip, @@ -137,7 +131,9 @@ static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane, return ret; if (!plane_state->visible) - return -EINVAL; + return 0; + + drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2); if (!pipe->funcs || !pipe->funcs->check) return 0;