CVE-2022-49687 virtio_net: fix xdp_rxq_info bug after suspend/resume
A missing unregister call in the virtio_net driver during suspend/resume causes a kernel warning and potential crash when bringing the interface down.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-49687?
CVE-2022-49687 is a high-severity vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
virtio_net: fix xdp_rxq_info bug after suspend/resume
The following sequence currently causes a driver bug warning when using virtio_net:
# ip link set eth0 up # echo mem > /sys/power/state (or e.g. # rtcwake -s 10 -m mem) <resume> # ip link set eth0 down
Missing register, driver bug WARNING: CPU: 0 PID: 375 at net/core/xdp.c:138 xdp_rxq_info_unreg+0x58/0x60 Call trace: xdp_rxq_info_unreg+0x58/0x60 virtnet_close+0x58/0xac __dev_close_many+0xac/0x140 __dev_change_flags+0xd8/0x210 dev_change_flags+0x24/0x64 do_setlink+0x230/0xdd0 ...
This happens because virtnet_freeze() frees the receive_queue completely (including struct xdp_rxq_info) but does not call xdp_rxq_info_unreg(). Similarly, virtnet_restore() sets up the receive_queue again but does not call xdp_rxq_info_reg().
Actually, parts of virtnet_freeze_down() and virtnet_restore_up() are almost identical to virtnet_close() and virtnet_open(): only the calls to xdp_rxq_info_(un)reg() are missing. This means that we can fix this easily and avoid such problems in the future by just calling virtnet_close()/open() from the freeze/restore handlers.
Aside from adding the missing xdp_rxq_info calls the only difference is that the refill work is only cancelled if netif_running(). However, this should not make any functional difference since the refill work should only be active if the network interface is actually up.
Which versions are affected by CVE-2022-49687?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49687?
Apply the vendor's patch.
Is CVE-2022-49687 being exploited?
There is no known exploitation of CVE-2022-49687 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49687, GHSA-xf96-jxw3-9974, UBUNTU-CVE-2022-49687.