[PATCH 5.15 212/530] drm/virtio: Correct drm_gem_shmem_get_sg_table() error handling

[Greg Kroah-Hartman]

From: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>

[ Upstream commit 64b88afbd92fbf434759d1896a7cf705e1c00e79 ]

Previous commit fixed checking of the ERR_PTR value returned by
drm_gem_shmem_get_sg_table(), but it missed to zero out the shmem->pages,
which will crash virtio_gpu_cleanup_object(). Add the missing zeroing of
the shmem->pages.

Fixes: c24968734abf ("drm/virtio: Fix NULL vs IS_ERR checking in virtio_gpu_object_shmem_init")
Reviewed-by: Emil Velikov <emil.l.velikov@xxxxxxxxx>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
Link: http://patchwork.freedesktop.org/patch/msgid/20220630200726.1884320-2-dmitry.osipenko@xxxxxxxxxxxxx
Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/virtio/virtgpu_object.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c
index 248ecd3006c3..7e75fb0fc7bd 100644
--- a/drivers/gpu/drm/virtio/virtgpu_object.c
+++ b/drivers/gpu/drm/virtio/virtgpu_object.c
@@ -169,6 +169,7 @@ static int virtio_gpu_object_shmem_init(struct virtio_gpu_device *vgdev,
 	shmem->pages = drm_gem_shmem_get_sg_table(&bo->base);
 	if (IS_ERR(shmem->pages)) {
 		drm_gem_shmem_unpin(&bo->base);
+		shmem->pages = NULL;
 		return PTR_ERR(shmem->pages);
 	}
 
-- 
2.35.1