CVE-2023-53219

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> media: netup_unidvb: fix use-after-free at del_timer()<br /> <br /> When Universal DVB card is detaching, netup_unidvb_dma_fini()<br /> uses del_timer() to stop dma-&gt;timeout timer. But when timer<br /> handler netup_unidvb_dma_timeout() is running, del_timer()<br /> could not stop it. As a result, the use-after-free bug could<br /> happen. The process is shown below:<br /> <br /> (cleanup routine) | (timer routine)<br /> | mod_timer(&amp;dev-&gt;tx_sim_timer, ..)<br /> netup_unidvb_finidev() | (wait a time)<br /> netup_unidvb_dma_fini() | netup_unidvb_dma_timeout()<br /> del_timer(&amp;dma-&gt;timeout); |<br /> | ndev-&gt;pci_dev-&gt;dev //USE<br /> <br /> Fix by changing del_timer() to del_timer_sync().