When read access is performed using a readable code segment, the "conforming"
and "non-conforming" checks should not be done. As a result, read using
non-conforming readable code segment fails.
This is according to Intel SDM 5.6.1 ("Accessing Data in Code Segments").
The fix is not to perform the "non-conforming" checks if the access is not a
fetch.
Signed-off-by: Nadav Amit <[email protected]>
---
arch/x86/kvm/emulate.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index a46207a..694dfa7 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -661,8 +661,8 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
goto bad;
}
cpl = ctxt->ops->cpl(ctxt);
- if (!(desc.type & 8)) {
- /* data segment */
+ if (!fetch) {
+ /* data segment or readable code segment */
if (cpl > desc.dpl)
goto bad;
} else if ((desc.type & 8) && !(desc.type & 4)) {
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
