[2/3] KVM: fix segment_base() error checking.

Commit Message

Gleb Natapov Feb. 25, 2010, 10:43 a.m. UTC

None

Patch

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 558eb9a..49f5c7b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -229,7 +229,7 @@  unsigned long segment_base(u16 selector)
 	unsigned long table_base;
 	unsigned long v;
 
-	if (selector == 0)
+	if (!(selector & ~3))
 		return 0;
 
 	native_store_gdt(&gdt);
@@ -238,6 +238,8 @@  unsigned long segment_base(u16 selector)
 	if (selector & 4) {           /* from ldt */
 		u16 ldt_selector = kvm_read_ldt();
 
+		if (!(ldt_selector & ~3))
+			return 0;
 		table_base = segment_base(ldt_selector);
 	}
 	d = (struct desc_struct *)(table_base + (selector & ~7));