process: Set user stack pointer to NULL in execve handler
This fixes an Abort exception, when stack canary check is enabled.
JIRA:
@@ -1181,6 +1181,9 @@ static int process_execve(thread_t *current)
thread_t *parent = spawn->parent;
vm_map_t *map;
+ /* The old user stack is no longer valid */
+ current->ustack = NULL;
+
/* Restore kernel stack of parent thread */
if (parent != NULL) {
hal_memcpy(hal_cpuGetSP(parent->context), current->parentkstack + (hal_cpuGetSP(parent->context) - parent->kstack), parent->kstack + parent->kstacksz - hal_cpuGetSP(parent->context));
