From: Nick Mathewson <nickm@torproject.org>
Date: Tue, 18 Mar 2014 14:49:39 +0000 (-0400)
Subject: Fix a ubsan warning in addr_mask_get_bits
X-Git-Tag: tor-0.2.5.4-alpha~85^2~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=dfdeb6418d3d99e6e9099a3ad8ca83c206b52bdc;p=thirdparty%2Ftor.git

Fix a ubsan warning in addr_mask_get_bits

ubsan doesn't like us to do (1u<<32) when 32 is wider than
unsigned.  Fortunately, we already special-case
addr_mask_get_bits(0), so we can just change the loop bounds.
---

diff --git a/src/common/address.c b/src/common/address.c
index 69049fa0af..bb1a24419e 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -1585,7 +1585,7 @@ addr_mask_get_bits(uint32_t mask)
     return 0;
   if (mask == 0xFFFFFFFFu)
     return 32;
-  for (i=0; i<=32; ++i) {
+  for (i=1; i<=32; ++i) {
     if (mask == (uint32_t) ~((1u<<(32-i))-1)) {
       return i;
     }