MitigationPolicies in KUSER_SHARED

The KUSER_SHARED_DATA structure defines the layout of a data area that the kernel places at a pre-set address for sharing with user-mode software. Windows 8 turns an old member named NXSupportPolicy at offset 0x02D5 into UCHAR bit fields in union with MitigationPolicies as some sort of collective name:

Mask	Definition	Versions
0x03	UCHAR NXSupportPolicy : 2;	6.2 and higher
0x0C	UCHAR SEHValidationPolicy : 2;	6.2 and higher
0x30	UCHAR CurDirDevicesSkippedForDlls : 2;	6.2 and higher
	UCHAR Reserved : 2;	6.2 and higher

Microsoft defines the following as allowed values for the NXSupportPolicy:

0 for NX_SUPPORT_POLICY_ALWAYSOFF;
1 for NX_SUPPORT_POLICY_ALWAYSON;
2 for NX_SUPPORT_POLICY_OPTIN;
3 for NX_SUPPORT_POLICY_OPTOUT;

and another set for the SEHValidationPolicy:

0 for SEH_VALIDATION_POLICY_ON;
1 for SEH_VALIDATION_POLICY_OFF;
2 for SEH_VALIDATION_POLICY_TELEMETRY;
3 for SEH_VALIDATION_POLICY_DEFER.

MitigationPolicies in KUSER_SHARED_DATA