net: dsa: mt7530: leave the MDIO IRQ mappings to regmap-irq

Summary

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mt7530: leave the MDIO IRQ mappings to regmap-irq mt7530_remove_common() disposes the per-PHY interrupt mappings from .remove, but the regmap-irq chip that owns the domain is devm-registered, so its parent interrupt is only freed once .remove has returned. The switch's own regmap-irq thread can therefore still dispatch on a mapping that is already gone: irq_find_mapping() returns 0, irq_to_desc() returns NULL and handle_nested_irq() locks desc->lock without checking it. The attached PHYs have not given those interrupts back yet either, which the kernel warns about a moment before the fault. regmap_del_irq_chip() disposes the same mappings itself, after freeing the parent interrupt and before removing the domain, so there is nothing left for the driver to do here. Until it runs the descriptors stay alive, and a late dispatch on one of them is harmless: dsa_unregister_switch() has freed the PHY handlers by then, so handle_nested_irq() finds no action and returns.

Timeline

1. Oct 18, 2026, 3:18 PM UTCCVE published
2. Oct 19, 2026, 9:21 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 254f6b272e3b67bf31c42ee9da62a449d74d1478 · fixed in 2357c682f6eaf639dec88c68b3c0c93a3b802635; From 254f6b272e3b67bf31c42ee9da62a449d74d1478 · fixed in f306e465b5a2091cd3fe3dd0feb10cfc94cfb2f8; From 254f6b272e3b67bf31c42ee9da62a449d74d1478 · fixed in 0d80ba0a204c6a16bd7778b50de578dff107c0fe

• Linux Linux

  6.15

• KernelLinux

  From 6.15.0 · fixed in 6.18.55; From 6.19.0 · fixed in 7.2.9

References 3