drm/nouveau: prevent userspace from deleting client object

[ Upstream commit c966b6279f610a24ac1d42dcbe30e10fa61220b2 ]

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/nouveau/nouveau_usif.c b/drivers/gpu/drm/nouveau/nouveau_usif.c
index 08f9c6f..1fba386 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_usif.c
+++ b/drivers/gpu/drm/nouveau/nouveau_usif.c
@@ -313,7 +313,8 @@ usif_ioctl(struct drm_file *filp, void __user *user, u32 argc)
        if (!(ret = nvif_unpack(-ENOSYS, &data, &size, argv->v0, 0, 0, true))) {
                /* block access to objects not created via this interface */
                owner = argv->v0.owner;
-               if (argv->v0.object == 0ULL)
+               if (argv->v0.object == 0ULL &&
+                   argv->v0.type != NVIF_IOCTL_V0_DEL)
                        argv->v0.owner = NVDRM_OBJECT_ANY; /* except client */
                else
                        argv->v0.owner = NVDRM_OBJECT_USIF;