Changeset 101521 in vbox for trunk/src/VBox/VMM/VMMR0

Timestamp:

Oct 20, 2023 2:29:27 PM (14 months ago)

Author:

vboxsync

Message:

HMR0A.asm: The code handled Linux's read-only GDT in addition to the already existing support for PaX's KERNEXEC based variant. However, in contrast to upstream Linux's implementation, there's no writable alias mapping of the GDT available under PaX KERNEXEC. The CR0.WP toggling method must therefore be used in this case. Contribution from Mathias Krause. Thanks! bugref:8864

File:

• trunk/src/VBox/VMM/VMMR0/HMR0A.asm (modified) (1 diff)

trunk/src/VBox/VMM/VMMR0/HMR0A.asm

@@ -439 +439 @@
 ALIGNCODE(8)
 .gdt_readonly_or_need_writable:
-        test    edi, VMX_RESTORE_HOST_GDT_NEED_WRITABLE
-        jnz     .gdt_readonly_need_writable
+        test    edi, VMX_RESTORE_HOST_GDT_READ_ONLY
+        jz      .gdt_readonly_need_writable
 .gdt_readonly:
         mov     rcx, cr0