From: Jianglei Nie niejianglei2021@163.com
commit 540dfd188ea2940582841c1c220bd035a7db0e51 upstream.
nouveau_bo_init() is backed by ttm_bo_init() and ferries its return code back to the caller. On failures, ttm will call nouveau_bo_del_ttm() and free the memory.Thus, when nouveau_bo_init() returns an error, the gem object has already been released. Then the call to nouveau_bo_ref() will use the freed "nvbo->bo" and lead to a use-after-free bug.
We should delete the call to nouveau_bo_ref() to avoid the use-after-free.
Signed-off-by: Jianglei Nie niejianglei2021@163.com Reviewed-by: Lyude Paul lyude@redhat.com Signed-off-by: Lyude Paul lyude@redhat.com Fixes: 019cbd4a4feb ("drm/nouveau: Initialize GEM object before TTM object") Cc: Thierry Reding treding@nvidia.com Cc: stable@vger.kernel.org # v5.4+ Link: https://patchwork.freedesktop.org/patch/msgid/20220705132546.2247677-1-nieji... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/nouveau/nouveau_prime.c | 1 - 1 file changed, 1 deletion(-)
--- a/drivers/gpu/drm/nouveau/nouveau_prime.c +++ b/drivers/gpu/drm/nouveau/nouveau_prime.c @@ -89,7 +89,6 @@ struct drm_gem_object *nouveau_gem_prime ret = nouveau_bo_init(nvbo, size, align, NOUVEAU_GEM_DOMAIN_GART, sg, robj); if (ret) { - nouveau_bo_ref(NULL, &nvbo); obj = ERR_PTR(ret); goto unlock; }