CVE-2026-45946power: supply: ab8500: Fix use-after-free in power_supply_changed()

Official description

In the Linux kernel, the following vulnerability has been resolved: power: supply: ab8500: Fix use-after-free in power_supply_changed() Using the `devm_` variant for requesting IRQ _before_ the `devm_` variant for allocating/registering the `power_supply` handle, means that the `power_supply` handle will be deallocated/unregistered _before_ the interrupt handler (since `devm_` naturally deallocates in reverse allocation order). This means that during removal, there is a race condition where an interrupt can fire just _after_ the `power_supply` handle has been freed, *but* just _before_ the corresponding unregistration of the IRQ handler has run. This will lead to the IRQ handler calling `power_supply_changed()` with a freed `power_supply` handle. Which usually crashes the system or otherwise silently corrupts the memory... Note that there is a similar situation which can also happen during `probe()`; the possibility of an interrupt firing _before_ registering the `power_supply` handle. This would then lead to the nasty situation of using the `power_supply` handle *uninitialized* in `power_supply_changed()`. Commit 1c1f13a006ed ("power: supply: ab8500: Move to componentized binding") introduced this issue during a refactorization. Fix this racy use-after-free by making sure the IRQ is requested _after_ the registration of the `power_supply` handle.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/43cbb78ee047b9b12d096d40e3be265969d4c1f8
• https://git.kernel.org/stable/c/551672981fe227122258a25a385a05f5c0746ad6
• https://git.kernel.org/stable/c/f50433f2603def08b21a4bf2fd238687fb5cbde9
• https://git.kernel.org/stable/c/847eeb6c0efcd76c7def73857cf798a4fcd8f79b
• https://git.kernel.org/stable/c/709db4b476e254579d9c48ec34d397a41ca0c407
• https://git.kernel.org/stable/c/46dbda27b028d78087667e8280966b99cec015ca
• https://git.kernel.org/stable/c/c4af8a98bb52825a5331ae1d0604c0ea6956ba4b