| Message ID | 20190226214451.195123-1-ebiggers@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] drm/vgem: fix use-after-free when drm_gem_handle_create() fails | expand |
On 2/26/19 1:44 PM, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > If drm_gem_handle_create() fails in vgem_gem_create(), then the > drm_vgem_gem_object is freed twice: once when the reference is dropped > by drm_gem_object_put_unlocked(), and again by __vgem_gem_destroy(). > > This was hit by syzkaller using fault injection. > > Fix it by skipping the second free. > > Reported-by: syzbot+e73f2fb5ed5a5df36d33@syzkaller.appspotmail.com > Fixes: af33a9190d02 ("drm/vgem: Enable dmabuf import interfaces") > Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Laura Abbott <labbott@redhat.com> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: stable@vger.kernel.org > Signed-off-by: Eric Biggers <ebiggers@google.com> > --- > drivers/gpu/drm/vgem/vgem_drv.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c > index 5930facd6d2d8..11a8f99ba18c5 100644 > --- a/drivers/gpu/drm/vgem/vgem_drv.c > +++ b/drivers/gpu/drm/vgem/vgem_drv.c > @@ -191,13 +191,9 @@ static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, > ret = drm_gem_handle_create(file, &obj->base, handle); > drm_gem_object_put_unlocked(&obj->base); > if (ret) > - goto err; > + return ERR_PTR(ret); > > return &obj->base; > - > -err: > - __vgem_gem_destroy(obj); > - return ERR_PTR(ret); > } > > static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev, > Acked-by: Laura Abbott <labbott@redhat.com>
On 02/26, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > If drm_gem_handle_create() fails in vgem_gem_create(), then the > drm_vgem_gem_object is freed twice: once when the reference is dropped > by drm_gem_object_put_unlocked(), and again by __vgem_gem_destroy(). > > This was hit by syzkaller using fault injection. > > Fix it by skipping the second free. > > Reported-by: syzbot+e73f2fb5ed5a5df36d33@syzkaller.appspotmail.com > Fixes: af33a9190d02 ("drm/vgem: Enable dmabuf import interfaces") > Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Laura Abbott <labbott@redhat.com> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: stable@vger.kernel.org > Signed-off-by: Eric Biggers <ebiggers@google.com> > --- > drivers/gpu/drm/vgem/vgem_drv.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c > index 5930facd6d2d8..11a8f99ba18c5 100644 > --- a/drivers/gpu/drm/vgem/vgem_drv.c > +++ b/drivers/gpu/drm/vgem/vgem_drv.c > @@ -191,13 +191,9 @@ static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, > ret = drm_gem_handle_create(file, &obj->base, handle); > drm_gem_object_put_unlocked(&obj->base); > if (ret) > - goto err; > + return ERR_PTR(ret); > > return &obj->base; > - > -err: > - __vgem_gem_destroy(obj); > - return ERR_PTR(ret); > } > > static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev, > -- > 2.21.0.rc2.261.ga7da99ff1b-goog > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel Applied to drm-misc-fixes. Thanks
diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index 5930facd6d2d8..11a8f99ba18c5 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -191,13 +191,9 @@ static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, ret = drm_gem_handle_create(file, &obj->base, handle); drm_gem_object_put_unlocked(&obj->base); if (ret) - goto err; + return ERR_PTR(ret); return &obj->base; - -err: - __vgem_gem_destroy(obj); - return ERR_PTR(ret); } static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,