A single fix targeting the MHI host stack:

Browse source

- Since the commit 1227d2a20c ("bus: mhi: host: Move IRQ allocation to
    controller registration phase"), the MHI context gets freed during
    mhi_unregister_controller(). But when the MHI IRQs are shared, the IRQ
    handler may get invoked during __free_irq() if CONFIG_DEBUG_SHIRQ is set.
    In that case, there will be a null pointer dereference because of trying to
    use the freed context struct.
 
    So for fixing the issue, let's check for the existence of the context struct
    at the start of the handler before handling the IRQ.
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Merge tag 'mhi-fixes-for-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi into char-misc-linus

Manivannan writes:
  "A single fix targeting the MHI host stack:

    - Since the commit 1227d2a20c ("bus: mhi: host: Move IRQ allocation to
      controller registration phase"), the MHI context gets freed during
      mhi_unregister_controller(). But when the MHI IRQs are shared, the IRQ
      handler may get invoked during __free_irq() if CONFIG_DEBUG_SHIRQ is set.
      In that case, there will be a null pointer dereference because of trying to
      use the freed context struct.

      So for fixing the issue, let's check for the existence of the context struct
      at the start of the handler before handling the IRQ."

* tag 'mhi-fixes-for-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi:
  bus: mhi: host: Fix up null pointer access in mhi_irq_handler

...

This commit is contained in:

Greg Kroah-Hartman 2022-08-30 16:13:32 +02:00

parent c063643cb3 acc5495bf7

commit 5ef251b9b7

1 changed files with 16 additions and 3 deletions

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drivers/bus/mhi/host/main.c

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