CVE-2024-56699: s390/pci: Fix potential double remove of hotplug slot
Description
In the Linux kernel, the following vulnerability has been resolved:
s390/pci: Fix potential double remove of hotplug slot
In commit 6ee600bfbe0f ("s390/pci: remove hotplug slot when releasing the
device") the zpci_exit_slot() was moved from zpci_device_reserved() to
zpci_release_device() with the intention of keeping the hotplug slot
around until the device is actually removed.
Now zpci_release_device() is only called once all references are
dropped. Since the zPCI subsystem only drops its reference once the
device is in the reserved state it follows that zpci_release_device()
must only deal with devices in the reserved state. Despite that it
contains code to tear down from both configured and standby state. For
the standby case this already includes the removal of the hotplug slot
so would cause a double removal if a device was ever removed in
either configured or standby state.
Instead of causing a potential double removal in a case that should
never happen explicitly WARN_ON() if a device in non-reserved state is
released and get rid of the dead code cases.
Classification
CVE ID: CVE-2024-56699
Affected Products
Vendor: Linux
Product: Linux
Exploit Prediction Scoring System (EPSS)
EPSS Score: 0.05% (probability of being exploited)
EPSS Percentile: 17.83% (scored less or equal to compared to others)
EPSS Date: 2025-02-04 (when was this score calculated)
References
https://git.kernel.org/stable/c/c1489651071ab1be46d2af1da8adb15c9fc3c069https://git.kernel.org/stable/c/371bd905599d18da62d75e3974acbf6a41e315c7
https://git.kernel.org/stable/c/c4a585e952ca403a370586d3f16e8331a7564901