From: Eric Biggers <ebigg...@google.com> If drm_gem_handle_create() fails in vkms_gem_create(), then the vkms_gem_object is freed twice: once when the reference is dropped by drm_gem_object_put_unlocked(), and again by the extra calls to drm_gem_object_release() and kfree().
Fix it by skipping the second release and free. This bug was originally found in the vgem driver by syzkaller using fault injection, but I noticed it's also present in the vkms driver. Fixes: 559e50fd34d1 ("drm/vkms: Add dumb operations") Cc: Rodrigo Siqueira <rodrigosiqueiram...@gmail.com> Cc: Haneen Mohammed <hamohammed...@gmail.com> Cc: Daniel Vetter <daniel.vet...@ffwll.ch> Cc: Chris Wilson <ch...@chris-wilson.co.uk> Cc: sta...@vger.kernel.org Signed-off-by: Eric Biggers <ebigg...@google.com> --- drivers/gpu/drm/vkms/vkms_gem.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/gpu/drm/vkms/vkms_gem.c b/drivers/gpu/drm/vkms/vkms_gem.c index 138b0bb325cf9..69048e73377dc 100644 --- a/drivers/gpu/drm/vkms/vkms_gem.c +++ b/drivers/gpu/drm/vkms/vkms_gem.c @@ -111,11 +111,8 @@ struct drm_gem_object *vkms_gem_create(struct drm_device *dev, ret = drm_gem_handle_create(file, &obj->gem, handle); drm_gem_object_put_unlocked(&obj->gem); - if (ret) { - drm_gem_object_release(&obj->gem); - kfree(obj); + if (ret) return ERR_PTR(ret); - } return &obj->gem; } -- 2.21.0.rc2.261.ga7da99ff1b-goog _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel