From: Xiaomeng Tong Date: Sun, 27 Mar 2022 05:09:45 +0000 (+0800) Subject: virtio-gpu: fix a missing check to avoid NULL dereference X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=39caef09666c1d8274abf9472c72bcac236dc5fb;p=linux.git virtio-gpu: fix a missing check to avoid NULL dereference [ Upstream commit bd63f11f4c3c46afec07d821f74736161ff6e526 ] 'cache_ent' could be set NULL inside virtio_gpu_cmd_get_capset() and it will lead to a NULL dereference by a lately use of it (i.e., ptr = cache_ent->caps_cache). Fix it with a NULL check. Fixes: 62fb7a5e10962 ("virtio-gpu: add 3d/virgl support") Signed-off-by: Xiaomeng Tong Reviewed-by: Chia-I Wu Link: http://patchwork.freedesktop.org/patch/msgid/20220327050945.1614-1-xiam0nd.tong@gmail.com [ kraxel: minor codestyle fixup ] Signed-off-by: Gerd Hoffmann Signed-off-by: Sasha Levin --- diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index 5c1ad1596889b..15c3e63db396d 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -512,8 +512,10 @@ static int virtio_gpu_get_caps_ioctl(struct drm_device *dev, spin_unlock(&vgdev->display_info_lock); /* not in cache - need to talk to hw */ - virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver, - &cache_ent); + ret = virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver, + &cache_ent); + if (ret) + return ret; virtio_gpu_notify(vgdev); copy_exit: