From 39caef09666c1d8274abf9472c72bcac236dc5fb Mon Sep 17 00:00:00 2001 From: Xiaomeng Tong Date: Sun, 27 Mar 2022 13:09:45 +0800 Subject: [PATCH] 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 --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index 5c1ad15..15c3e63 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: -- 2.7.4