CVE-2022-50504

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> powerpc/rtas: avoid scheduling in rtas_os_term()<br /> <br /> It&amp;#39;s unsafe to use rtas_busy_delay() to handle a busy status from<br /> the ibm,os-term RTAS function in rtas_os_term():<br /> <br /> Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b<br /> BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:618<br /> in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0<br /> preempt_count: 2, expected: 0<br /> CPU: 7 PID: 1 Comm: swapper/0 Tainted: G D 6.0.0-rc5-02182-gf8553a572277-dirty #9<br /> Call Trace:<br /> [c000000007b8f000] [c000000001337110] dump_stack_lvl+0xb4/0x110 (unreliable)<br /> [c000000007b8f040] [c0000000002440e4] __might_resched+0x394/0x3c0<br /> [c000000007b8f0e0] [c00000000004f680] rtas_busy_delay+0x120/0x1b0<br /> [c000000007b8f100] [c000000000052d04] rtas_os_term+0xb8/0xf4<br /> [c000000007b8f180] [c0000000001150fc] pseries_panic+0x50/0x68<br /> [c000000007b8f1f0] [c000000000036354] ppc_panic_platform_handler+0x34/0x50<br /> [c000000007b8f210] [c0000000002303c4] notifier_call_chain+0xd4/0x1c0<br /> [c000000007b8f2b0] [c0000000002306cc] atomic_notifier_call_chain+0xac/0x1c0<br /> [c000000007b8f2f0] [c0000000001d62b8] panic+0x228/0x4d0<br /> [c000000007b8f390] [c0000000001e573c] do_exit+0x140c/0x1420<br /> [c000000007b8f480] [c0000000001e586c] make_task_dead+0xdc/0x200<br /> <br /> Use rtas_busy_delay_time() instead, which signals without side effects<br /> whether to attempt the ibm,os-term RTAS call again.