From: "Edgar E. Iglesias" <[email protected]>
Reviewed-by: Peter Crosthwaite <[email protected]>
Signed-off-by: Edgar E. Iglesias <[email protected]>
---
target-arm/op_helper.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c
index c2b4bf0..e95a7f4 100644
--- a/target-arm/op_helper.c
+++ b/target-arm/op_helper.c
@@ -389,6 +389,7 @@ void HELPER(exception_return)(CPUARMState *env)
unsigned int spsr_idx = aarch64_banked_spsr_index(1);
uint32_t spsr = env->banked_spsr[spsr_idx];
int new_el, i;
+ int cur_el = arm_current_pl(env);
if (env->pstate & PSTATE_SP) {
env->sp_el[1] = env->xregs[31];
@@ -410,8 +411,11 @@ void HELPER(exception_return)(CPUARMState *env)
env->regs[15] = env->elr_el[1] & ~0x1;
} else {
new_el = extract32(spsr, 2, 2);
- if (new_el > 1) {
- /* Return to unimplemented EL */
+ if (new_el > cur_el
+ || (new_el == 2 && !arm_feature(env, ARM_FEATURE_EL2))) {
+ /* Disallow return to an EL which is unimplemented or higher
+ * than the current one.
+ */
goto illegal_return;
}
if (extract32(spsr, 1, 1)) {
--
1.8.3.2
