| Message ID | 20211213053912.2167066-1-jiasheng@iscas.ac.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/ast: potential dereference of null pointer | expand |
Hi, thanks for the patch. Am 13.12.21 um 06:39 schrieb Jiasheng Jiang: > he return value of kzalloc() needs to be checked. 'The' > To avoid use of null pointer '&ast_state->base' in case of the > failure of alloc. > > Fixes: f0adbc382b8b ("drm/ast: Allocate initial CRTC state of the correct size") > Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> > --- > drivers/gpu/drm/ast/ast_mode.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c > index 36d9575aa27b..67f8e3f90ea2 100644 > --- a/drivers/gpu/drm/ast/ast_mode.c > +++ b/drivers/gpu/drm/ast/ast_mode.c > @@ -1120,7 +1120,8 @@ static void ast_crtc_reset(struct drm_crtc *crtc) > if (crtc->state) > crtc->funcs->atomic_destroy_state(crtc, crtc->state); > > - __drm_atomic_helper_crtc_reset(crtc, &ast_state->base); > + if (ast_state) > + __drm_atomic_helper_crtc_reset(crtc, &ast_state->base); If ast_state is NULL, __drm_atomic_helper_crtc_reset() has to be called with a state of NULL. Otherwise the reset might leave the dangling pointer in the CRTC's state field. Best regards Thomas > } > > static struct drm_crtc_state * >
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c index 36d9575aa27b..67f8e3f90ea2 100644 --- a/drivers/gpu/drm/ast/ast_mode.c +++ b/drivers/gpu/drm/ast/ast_mode.c @@ -1120,7 +1120,8 @@ static void ast_crtc_reset(struct drm_crtc *crtc) if (crtc->state) crtc->funcs->atomic_destroy_state(crtc, crtc->state); - __drm_atomic_helper_crtc_reset(crtc, &ast_state->base); + if (ast_state) + __drm_atomic_helper_crtc_reset(crtc, &ast_state->base); } static struct drm_crtc_state *
he return value of kzalloc() needs to be checked. To avoid use of null pointer '&ast_state->base' in case of the failure of alloc. Fixes: f0adbc382b8b ("drm/ast: Allocate initial CRTC state of the correct size") Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> --- drivers/gpu/drm/ast/ast_mode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)