CVE-2023-52439

In the Linux kernel, the following vulnerability has been resolved: uio: Fix use-after-free in uio_open core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uio_release and put_device, the idev will be double freed. To address this issue, we can get idev atomic & inc idev reference with minor_lock.

• linux linux kernel (> 4.18.0 < 4.19.306) • linux linux kernel (>= 4.20.0 < 5.4.268) • linux linux kernel (>= 5.5.0 < 5.10.209) • linux linux kernel (>= 5.11.0 < 5.15.148) • linux linux kernel (>= 5.16.0 < 6.1.74) • linux linux kernel (>= 6.2.0 < 6.6.13) • linux linux kernel (>= 6.7.0 < 6.7.1) • linux linux kernel 4.18