From: Roger Dingledine <arma@torproject.org>
Date: Mon, 29 Nov 2004 08:40:24 +0000 (+0000)
Subject: clean up the previous underflow check, and also point out
X-Git-Tag: debian-version-0.0.8+0.0.9rc3-1~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=671a2de762e7b151710484cef2973bb6ef42ec66;p=thirdparty%2Ftor.git

clean up the previous underflow check, and also point out
yet another one that may be a problem. nick?


svn:r3016
---

diff --git a/src/common/log.c b/src/common/log.c
index 4e4bc1862b..82211c98c9 100644
--- a/src/common/log.c
+++ b/src/common/log.c
@@ -122,10 +122,8 @@ static INLINE char *format_msg(char *buf, size_t buf_len,
   size_t n;
   int r;
   char *end_of_prefix;
-  if (buf_len < 2) { /* prevent integer underflow */
-    tor_assert(0);
-    exit(1);
-  }
+
+  tor_assert(buf_len >= 2); /* prevent integer underflow */
   buf_len -= 2; /* subtract 2 characters so we have room for \n\0 */
 
   n = _log_prefix(buf, buf_len, severity);
@@ -141,7 +139,8 @@ static INLINE char *format_msg(char *buf, size_t buf_len,
 
   r = tor_vsnprintf(buf+n,buf_len-n,format,ap);
   if (r < 0) {
-    n = buf_len-2;
+    n = buf_len-2; /* XXX is this line redundant with the -=2 above,
+                      and also a source of underflow danger? */
     strlcpy(buf+buf_len-TRUNCATED_STR_LEN-1, TRUNCATED_STR,
             buf_len-(buf_len-TRUNCATED_STR_LEN-1));
   } else {