4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric Biggers <[email protected]> commit 21d2b122732318b48c10b7262e15595ce54511d3 upstream. 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: [email protected] Fixes: af33a9190d02 ("drm/vgem: Enable dmabuf import interfaces") Reviewed-by: Chris Wilson <[email protected]> Cc: Laura Abbott <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: [email protected] Signed-off-by: Eric Biggers <[email protected]> Acked-by: Laura Abbott <[email protected]> Signed-off-by: Rodrigo Siqueira <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Maxime Ripard <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/vgem/vgem_drv.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -192,13 +192,9 @@ static struct drm_gem_object *vgem_gem_c 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,
