CVE-2021-47558

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

net: stmmac: Disable Tx queues when reconfiguring the interface

The Tx queues were not disabled in situations where the driver needed to

stop the interface to apply a new configuration. This could result in a

kernel panic when doing any of the 3 following actions:

* reconfiguring the number of queues (ethtool -L)

* reconfiguring the size of the ring buffers (ethtool -G)

* installing/removing an XDP program (ip l set dev ethX xdp)

Prevent the panic by making sure netif_tx_disable is called when stopping

an interface.

Without this patch, the following kernel panic can be observed when doing

any of the actions above:

Unable to handle kernel paging request at virtual address ffff80001238d040

[....]

Call trace:

dwmac4_set_addr+0x8/0x10

dev_hard_start_xmit+0xe4/0x1ac

sch_direct_xmit+0xe8/0x39c

__dev_queue_xmit+0x3ec/0xaf0

dev_queue_xmit+0x14/0x20

[...]

[ end trace 0000000000000002 ]---

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References