From: Toni Wilen <twilen@winuae.net>
Date: Sun, 16 Apr 2017 19:11:45 +0000 (+0300)
Subject: Halt if initial PC is corrupt or odd.
X-Git-Tag: 3500~58
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=2207757596d795b04822e4b47b4c7a83d5c58842;p=francis%2Fwinuae.git

Halt if initial PC is corrupt or odd.
---

diff --git a/include/newcpu.h b/include/newcpu.h
index 0c3ac3a9..ebee8729 100644
--- a/include/newcpu.h
+++ b/include/newcpu.h
@@ -693,6 +693,7 @@ extern bool can_cpu_tracer (void);
 #define CPU_HALT_PCI_CONFLICT 8
 #define CPU_HALT_CPU_STUCK 9
 #define CPU_HALT_SSP_IN_NON_EXISTING_ADDRESS 10
+#define CPU_HALT_INVALID_START_ADDRESS 11
 
 void cpu_semaphore_get(void);
 void cpu_semaphore_release(void);
diff --git a/newcpu.cpp b/newcpu.cpp
index b5e26d37..7a99c546 100644
--- a/newcpu.cpp
+++ b/newcpu.cpp
@@ -5571,6 +5571,14 @@ void m68k_go (int may_quit)
 		event_wait = true;
 		unset_special(SPCFLAG_MODE_CHANGE);
 
+		if (!regs.halted) {
+			// check that PC points to something that looks like memory.
+			uaecptr pc = m68k_getpc();
+			addrbank *ab = get_mem_bank_real(pc);
+			if (ab == NULL || ab == &dummy_bank || (!currprefs.cpu_compatible && !valid_address(pc, 2)) || (pc & 1)) {
+				cpu_halt(CPU_HALT_INVALID_START_ADDRESS);
+			}
+		}
 		if (regs.halted) {
 			cpu_halt (regs.halted);
 			if (regs.halted < 0) {