net: dsa: mxl862xx: disable the stats poll on teardown

Summary

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mxl862xx: disable the stats poll on teardown mxl862xx_setup() arms the stats poll before mxl862xx_setup_mdio(), and nothing stops it until dsa_register_switch() has returned an error to mxl862xx_probe(). DSA frees the dsa_port list before it returns, so a poll that fires once .setup or a later step of dsa_tree_setup() has failed walks freed ports. On shutdown the user ports stay registered, and the WORK_STOPPED flag test in mxl862xx_get_stats64() is not atomic with the cancel in mxl862xx_shutdown(), so a re-arm that read the flag before it was set queues the poll after cancel_delayed_work_sync() has returned. Arm the poll once .setup has succeeded and stop it from a .teardown op, which DSA calls on unregister and after a failed registration, in both cases before it frees the ports. Use disable_delayed_work_sync() there and in shutdown(): it drains a running poll as the cancel did and turns every later attempt to queue the work into a no-op, so the re-arm cannot bring the poll back. remove() and the probe error path only set WORK_STOPPED, which crc_err_work tests before it walks the ports.

Timeline

1. Oct 6, 2026, 8:46 AM UTCCVE published
2. Oct 19, 2026, 9:17 AM UTCRecord last updated

Affected versions

• Linux Linux

  From a21d33a5265f0b31d935a8b9b2b6faefb5185911 · fixed in 97df811a11d4f76bc2ffe67b6bf730263f56c668; From a21d33a5265f0b31d935a8b9b2b6faefb5185911 · fixed in 9e92ad4630f5dd1838ce6bbe6b1bd2c73d34de36

• Linux Linux

  7.1

• KernelLinux

  From 7.1.0 · fixed in 7.2.8

References 2