CVE-2023-52994 Information

Description

In the Linux kernel the following vulnerability has been resolved:

acpi: Fix suspend with Xen PV

Commit f1e525009493 (�/boot: Skip realmode init code when running as Xen PV guest) missed one code path accessing real_mode_header leading to dereferencing NULL when suspending the system under Xen:

[  348.284004] PM: suspend entry (deep)
[  348.289532] Filesystems sync: 0.005 seconds
[  348.291545] Freezing user space processes ... (elapsed 0.000 seconds) done.
[  348.292457] OOM killer disabled.
[  348.292462] Freezing remaining freezable tasks ... (elapsed 0.104 seconds) done.
[  348.396612] printk: Suspending console(s) (use no_console_suspend to debug)
[  348.749228] PM: suspend devices took 0.352 seconds
[  348.769713] ACPI: EC: interrupt blocked
[  348.816077] BUG: kernel NULL pointer dereference address: 000000000000001c
[  348.816080] PF: supervisor read access in kernel mode
[  348.816081] PF: error_code(0x0000) - not-present page
[  348.816083] PGD 0 P4D 0
[  348.816086] Oops: 0000 [1] PREEMPT SMP NOPTI
[  348.816089] CPU: 0 PID: 6764 Comm: systemd-sleep Not tainted 6.1.3-1.fc32.qubes.x86_64 1
[  348.816092] Hardware name: Star Labs StarBook/StarBook BIOS 8.01 07/03/2022
[  348.816093] RIP: e030:acpi_get_wakeup_address+0xc/0x20

Fix that by adding an optional acpi callback allowing to skip setting the wakeup address as in the Xen PV case this will be handled by the hypervisor anyway.

Reference

https://git.kernel.org/stable/c/b96903b7fc8c82ddfd92df4cdd83db3e567da0a5 https://git.kernel.org/stable/c/fe0ba8c23f9a35b0307eb662f16dd3a75fcdae41