ofp-parse: Fix small memory leak when calling parse_ofp_meter_mod_str().

The function parse_ofp_meter_mod_str() allocates a buffer called
'bands', which parse_ofp_meter_mod_str__() then steals for the member
'mm->meter.bands'.  Calling functions didn't free that stolen value and
the comments for those function didn't indicate that was necessary.

Found by valgrind.

Signed-off-by: Justin Pettit <jpettit@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>

diff --git a/lib/ofp-parse.c b/lib/ofp-parse.c
index 528b75b4f4e179535537f23d8c4ceffb66d19424..725fc41e063ccb2b15301e5760f9a12c3292fdac 100644 (file)
--- a/lib/ofp-parse.c
+++ b/lib/ofp-parse.c
@@ -754,6 +754,8 @@ parse_ofp_packet_out_str(struct ofputil_packet_out *po, const char *str_,
     return error;
 }
 
+/* Parse a string representation of a meter modification message to '*mm'.
+ * If successful, 'mm->meter.bands' must be free()d by the caller. */
 static char * OVS_WARN_UNUSED_RESULT
 parse_ofp_meter_mod_str__(struct ofputil_meter_mod *mm, char *string,
                           struct ofpbuf *bands, int command,
@@ -795,6 +797,9 @@ parse_ofp_meter_mod_str__(struct ofputil_meter_mod *mm, char *string,
     mm->command = command;
     mm->meter.meter_id = 0;
     mm->meter.flags = 0;
+    mm->meter.n_bands = 0;
+    mm->meter.bands = NULL;
+
     if (fields & F_BANDS) {
         band_str = strstr(string, "band");
         if (!band_str) {
@@ -945,9 +950,6 @@ parse_ofp_meter_mod_str__(struct ofputil_meter_mod *mm, char *string,
                 }
             }
         }
-    } else {
-        mm->meter.n_bands = 0;
-        mm->meter.bands = NULL;
     }
 
     return NULL;
@@ -957,7 +959,8 @@ parse_ofp_meter_mod_str__(struct ofputil_meter_mod *mm, char *string,
  * page) into 'mm' for sending the specified meter_mod 'command' to a switch.
  *
  * Returns NULL if successful, otherwise a malloc()'d string describing the
- * error.  The caller is responsible for freeing the returned string. */
+ * error.  The caller is responsible for freeing the returned string.
+ * If successful, 'mm->meter.bands' must be free()d by the caller. */
 char * OVS_WARN_UNUSED_RESULT
 parse_ofp_meter_mod_str(struct ofputil_meter_mod *mm, const char *str_,
                         int command, enum ofputil_protocol *usable_protocols)

diff --git a/utilities/ovs-ofctl.c b/utilities/ovs-ofctl.c
index ad862efe3e398564a5ac47faf3cb461d38098918..6fb2cc08de50307ad562946cacffb64706cab94c 100644 (file)
--- a/utilities/ovs-ofctl.c
+++ b/utilities/ovs-ofctl.c
@@ -3699,11 +3699,13 @@ ofctl_meter_mod__(const char *bridge, const char *str, int command)
         usable_protocols = OFPUTIL_P_OF13_UP;
         mm.command = command;
         mm.meter.meter_id = OFPM13_ALL;
+        mm.meter.bands = NULL;
     }
 
     protocol = open_vconn_for_flow_mod(bridge, &vconn, usable_protocols);
     version = ofputil_protocol_to_ofp_version(protocol);
     transact_noreply(vconn, ofputil_encode_meter_mod(version, &mm));
+    free(mm.meter.bands);
     vconn_close(vconn);
 }
 
@@ -3726,12 +3728,14 @@ ofctl_meter_request__(const char *bridge, const char *str,
     } else {
         usable_protocols = OFPUTIL_P_OF13_UP;
         mm.meter.meter_id = OFPM13_ALL;
+        mm.meter.bands = NULL;
     }
 
     protocol = open_vconn_for_flow_mod(bridge, &vconn, usable_protocols);
     version = ofputil_protocol_to_ofp_version(protocol);
     dump_transaction(vconn, ofputil_encode_meter_request(version, type,
                                                          mm.meter.meter_id));
+    free(mm.meter.bands);
     vconn_close(vconn);
 }