tor

commit b058f64cc002b44e6dd48616ca3163a01c3f3e14
parent 9e65e7a36f6f7b18164d0e76fe25f0c32b31aaec
Author: Nick Mathewson <nickm@torproject.org>
Date:   Thu, 27 Sep 2018 16:30:02 -0400

Detect an unlikely integer overflow.

Diffstat:
M
src/feature/stats/geoip_stats.c
 | 
5
++++-
M
src/lib/geoip/country.h
 | 
2
++

2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/src/feature/stats/geoip_stats.c b/src/feature/stats/geoip_stats.c
@@ -265,7 +265,10 @@ geoip_note_client_seen(geoip_client_action_t action,
     int country_idx = geoip_get_country_by_addr(addr);
     if (country_idx < 0)
       country_idx = 0; /** unresolved requests are stored at index 0. */
-    increment_v3_ns_request(country_idx);
+    IF_BUG_ONCE(country_idx > COUNTRY_MAX) {
+      return;
+    }
+    increment_v3_ns_request((country_t) country_idx);
   }
 }
 
diff --git a/src/lib/geoip/country.h b/src/lib/geoip/country.h
@@ -11,4 +11,6 @@
 /** A signed integer representing a country code. */
 typedef int16_t country_t;
 
+#define COUNTRY_MAX INT16_MAX
+
 #endif