altos/stm: Validate current task SP in interrupt by looking at PSP

[fw/altos] / src / stm / ao_arch_funcs.h

diff --git a/src/stm/ao_arch_funcs.h b/src/stm/ao_arch_funcs.h
index 42f1a2e5d75c5aeb4680dbf12c7c9b0f039e9ebb..6b38032cc352a296b75731095d2fe10b76297f44 100644 (file)
--- a/src/stm/ao_arch_funcs.h
+++ b/src/stm/ao_arch_funcs.h
@@ -335,6 +335,13 @@ static inline void ao_arch_save_stack(void) {
 
 static inline void ao_arch_restore_stack(void) {
        uint32_t        sp;
+       uint32_t        control;
+
+       asm("mrs %0,control" : "=&r" (control));
+       control |= (1 << 1);
+       asm("msr control,%0" : : "r" (control));
+       asm("isb");
+
        sp = (uint32_t) ao_cur_task->sp;
 
        /* Switch stacks */
@@ -359,6 +366,22 @@ static inline void ao_arch_restore_stack(void) {
 #define HAS_SAMPLE_PROFILE 0
 #endif
 
+#if DEBUG
+#define HAS_ARCH_VALIDATE_CUR_STACK    1
+
+static inline void
+ao_validate_cur_stack(void)
+{
+       uint8_t         *psp;
+
+       asm("mrs %0,psp" : "=&r" (psp));
+       if (ao_cur_task &&
+           psp <= ao_cur_task->stack &&
+           psp >= ao_cur_task->stack - 256)
+               ao_panic(AO_PANIC_STACK);
+}
+#endif
+
 #if !HAS_SAMPLE_PROFILE
 #define HAS_ARCH_START_SCHEDULER       1
 
@@ -375,7 +398,14 @@ static inline void ao_arch_start_scheduler(void) {
 }
 #endif
 
-#define ao_arch_isr_stack()
+static inline void ao_arch_isr_stack(void) {
+       uint32_t        control;
+
+       asm("mrs %0,control" : "=&r" (control));
+       control &= ~(1 << 1);
+       asm("msr control,%0" : : "r" (control));
+       asm("isb");
+}
 
 #endif