In the Linux kernel, the following vulnerability has been resolved:
powerpc/rtas: avoid device tree lookups in rtasosterm()
rtasosterm() is called during panic. Its behavior depends on a couple of conditions in the /rtas node of the device tree, the traversal of which entails locking and local IRQ state changes. If the kernel panics while devtreelock is held, rtasos_term() as currently written could hang.
Instead of discovering the relevant characteristics at panic time, cache them in file-static variables at boot. Note the lookup for "ibm,extended-os-term" is converted to ofpropertyread_bool() since it is a boolean property, not an RTAS function token.
[mpe: Incorporate suggested change from Nick]
{
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50870.json"
}