From: Jeremy Hylton <jeremy@alum.mit.edu>
Date: Thu, 20 Dec 2001 02:07:36 +0000 (+0000)
Subject: Backport rev 2.301 to the 2.1 maintenance branch.
X-Git-Tag: v2.1.2c1~39
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=f7adf24280c05069432d0f2272a786e293c0e99c;p=thirdparty%2FPython%2Fcpython.git

Backport rev 2.301 to the 2.1 maintenance branch.

Add checks for stack underflow and overflow.
---

diff --git a/Python/ceval.c b/Python/ceval.c
index 72e4b6b7d697..0872c3e711a8 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -402,7 +402,9 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
 #define BASIC_POP()	(*--stack_pointer)
 
 #ifdef LLTRACE
-#define PUSH(v)		(BASIC_PUSH(v), lltrace && prtrace(TOP(), "push"))
+#define PUSH(v)		{ (void)(BASIC_PUSH(v), \
+                               lltrace && prtrace(TOP(), "push")); \
+                               assert(STACK_LEVEL() <= f->f_stacksize); }
 #define POP()		(lltrace && prtrace(TOP(), "pop"), BASIC_POP())
 #else
 #define PUSH(v)		BASIC_PUSH(v)
@@ -681,6 +683,8 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
 	w = NULL;
 
 	for (;;) {
+		assert(stack_pointer >= f->f_valuestack);	/* else underflow */
+		assert(STACK_LEVEL() <= f->f_stacksize);	/* else overflow */
 		/* Do periodic things.  Doing this every time through
 		   the loop would add too much overhead, so we do it
 		   only every Nth instruction.  We also do it if