Jianglei Nie
2022-Jul-05 13:26 UTC
[Nouveau] [PATCH] drm/nouveau: fix a use-after-free in nouveau_gem_prime_import_sg_table()
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 at 163.com>
---
drivers/gpu/drm/nouveau/nouveau_prime.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_prime.c
b/drivers/gpu/drm/nouveau/nouveau_prime.c
index 347488685f74..9608121e49b7 100644
--- a/drivers/gpu/drm/nouveau/nouveau_prime.c
+++ b/drivers/gpu/drm/nouveau/nouveau_prime.c
@@ -71,7 +71,6 @@ struct drm_gem_object
*nouveau_gem_prime_import_sg_table(struct drm_device *dev,
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;
}
--
2.25.1
Lyude Paul
2022-Jul-07 19:49 UTC
[Nouveau] [PATCH] drm/nouveau: fix a use-after-free in nouveau_gem_prime_import_sg_table()
Reviewed-by: Lyude Paul <lyude at redhat.com> Will push to the appropriate branch in a moment On Tue, 2022-07-05 at 21:25 +0800, Jianglei Nie wrote:> 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 at 163.com> > --- > ?drivers/gpu/drm/nouveau/nouveau_prime.c | 1 - > ?1 file changed, 1 deletion(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_prime.c > b/drivers/gpu/drm/nouveau/nouveau_prime.c > index 347488685f74..9608121e49b7 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_prime.c > +++ b/drivers/gpu/drm/nouveau/nouveau_prime.c > @@ -71,7 +71,6 @@ struct drm_gem_object > *nouveau_gem_prime_import_sg_table(struct drm_device *dev, > ????????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; > ????????}-- Cheers, Lyude Paul (she/her) Software Engineer at Red Hat