CVE-2026-46270
Description
In the Linux kernel, the following vulnerability has been resolved: power: supply: rt9455: 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()`. Fix this racy use-after-free by making sure the IRQ is requested _after_ the registration of the `power_supply` handle.
References
- https://git.kernel.org/stable/c/2178dc65d45e2f7bcaa8af8d80d100419bdab251
- https://git.kernel.org/stable/c/62d753b916bd500bb269b7078cdab73198ab4718
- https://git.kernel.org/stable/c/64e15155095f39f4dec9b4659da1238ef8fc54d4
- https://git.kernel.org/stable/c/721449a15170fc5f028a7576d7f65b9f60d53482
- https://git.kernel.org/stable/c/a39f8f06216f73ef40e71e2fe4ad071964c1fd36