CVE-2022-48808

Description

In the Linux kernel, the following vulnerability has been resolved:net: dsa: fix panic when DSA master device unbinds on shutdownRafael reports that on a system with LX2160A and Marvell DSA switches,if a reboot occurs while the DSA master (dpaa2-eth) is up, the followingpanic can be seen:systemd-shutdown[1]: Rebooting.Unable to handle kernel paging request at virtual address 00a0000800000041[00a0000800000041] address between user and kernel address rangesInternal error: Oops: 96000004 [#1] PREEMPT SMPCPU: 6 PID: 1 Comm: systemd-shutdow Not tainted 5.16.5-00042-g8f5585009b24 #32pc : dsa_slave_netdevice_event+0x130/0x3e4lr : raw_notifier_call_chain+0x50/0x6cCall trace: dsa_slave_netdevice_event+0x130/0x3e4 raw_notifier_call_chain+0x50/0x6c call_netdevice_notifiers_info+0x54/0xa0 __dev_close_many+0x50/0x130 dev_close_many+0x84/0x120 unregister_netdevice_many+0x130/0x710 unregister_netdevice_queue+0x8c/0xd0 unregister_netdev+0x20/0x30 dpaa2_eth_remove+0x68/0x190 fsl_mc_driver_remove+0x20/0x5c __device_release_driver+0x21c/0x220 device_release_driver_internal+0xac/0xb0 device_links_unbind_consumers+0xd4/0x100 __device_release_driver+0x94/0x220 device_release_driver+0x28/0x40 bus_remove_device+0x118/0x124 device_del+0x174/0x420 fsl_mc_device_remove+0x24/0x40 __fsl_mc_device_remove+0xc/0x20 device_for_each_child+0x58/0xa0 dprc_remove+0x90/0xb0 fsl_mc_driver_remove+0x20/0x5c __device_release_driver+0x21c/0x220 device_release_driver+0x28/0x40 bus_remove_device+0x118/0x124 device_del+0x174/0x420 fsl_mc_bus_remove+0x80/0x100 fsl_mc_bus_shutdown+0xc/0x1c platform_shutdown+0x20/0x30 device_shutdown+0x154/0x330 __do_sys_reboot+0x1cc/0x250 __arm64_sys_reboot+0x20/0x30 invoke_syscall.constprop.0+0x4c/0xe0 do_el0_svc+0x4c/0x150 el0_svc+0x24/0xb0 el0t_64_sync_handler+0xa8/0xb0 el0t_64_sync+0x178/0x17cIt can be seen from the stack trace that the problem is that thederegistration of the master causes a dev_close(), which gets notifiedas NETDEV_GOING_DOWN to dsa_slave_netdevice_event().But dsa_switch_shutdown() has already run, and this has unregistered theDSA slave interfaces, and yet, the NETDEV_GOING_DOWN handler attempts tocall dev_close_many() on those slave interfaces, leading to the problem.The previous attempt to avoid the NETDEV_GOING_DOWN on the master afterdsa_switch_shutdown() was called seems improper. Unregistering the slaveinterfaces is unnecessary and unhelpful. Instead, after the slaves havestopped being uppers of the DSA master, we can now reset to null themaster->dsa_ptr pointer, which will make DSA start ignoring all futurenotifier events on the master.

Risk Information

Associated Vulnerability

Patch Details

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234