From: Wolfram Sang <wsa+renesas@sang-engineering.com> stable inclusion from stable-v4.19.293 commit 97a2d55ead76358245b446efd87818e919196d7a bugzilla: https://gitee.com/src-openeuler/kernel/issues/ID0RG6 CVE: CVE-2023-53515 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 55c91fedd03d7b9cf0c5199b2eb12b9b8e95281a ] vm_dev has a separate lifecycle because it has a 'struct device' embedded. Thus, having a release callback for it is correct. Allocating the vm_dev struct with devres totally breaks this protection, though. Instead of waiting for the vm_dev release callback, the memory is freed when the platform_device is removed. Resulting in a use-after-free when finally the callback is to be called. To easily see the problem, compile the kernel with CONFIG_DEBUG_KOBJECT_RELEASE and unbind with sysfs. The fix is easy, don't use devres in this case. Found during my research about object lifetime problems. Fixes: 7eb781b1bbb7 ("virtio_mmio: add cleanup for virtio_mmio_probe") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Message-Id: <20230629120526.7184-1-wsa+renesas@sang-engineering.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- drivers/virtio/virtio_mmio.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 4cd9ea5c75be..555bc4634ac9 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -515,9 +515,7 @@ static void virtio_mmio_release_dev(struct device *_d) container_of(_d, struct virtio_device, dev); struct virtio_mmio_device *vm_dev = container_of(vdev, struct virtio_mmio_device, vdev); - struct platform_device *pdev = vm_dev->pdev; - - devm_kfree(&pdev->dev, vm_dev); + kfree(vm_dev); } /* Platform device */ @@ -537,7 +535,7 @@ static int virtio_mmio_probe(struct platform_device *pdev) resource_size(mem), pdev->name)) return -EBUSY; - vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL); + vm_dev = kzalloc(sizeof(*vm_dev), GFP_KERNEL); if (!vm_dev) return -ENOMEM; -- 2.39.2