core: ensure that GMatchInfo and GRegex objects are freed properly

In particular, g_regex_match() and g_regex_match_full() allocate a
match_info structure on both success and failure, so calling
g_match_info_free() only in the success case is insufficient.

BUG=None
TEST=Inspection

Change-Id: Iea76b5b5dc3ec48120e15601a5e2dd45322133d8

3 files changed, 37 insertions, 43 deletions

diff --git a/src/mm-generic-gsm.c b/src/mm-generic-gsm.c
index 78703042..82e51f67 100644
--- a/src/mm-generic-gsm.c
+++ b/src/mm-generic-gsm.c
@@ -2860,7 +2860,7 @@ handle_reg_status_response (MMGenericGsm *self,
     guint32 status = 0;
     gulong lac = 0, ci = 0;
     gint act = -1;
-    gboolean cgreg = FALSE;
+    gboolean cgreg = FALSE, parsed;
     guint i;
 
     /* Try to match the response */
@@ -2880,22 +2880,21 @@ handle_reg_status_response (MMGenericGsm *self,
     }
 
     /* And parse it */
-    if (!mm_gsm_parse_creg_response (match_info, &status, &lac, &ci, &act, &cgreg, error)) {
-        g_match_info_free (match_info);
-        return FALSE;
-    }
+    parsed = mm_gsm_parse_creg_response (match_info, &status, &lac, &ci, &act, &cgreg, error);
+    g_match_info_free (match_info);
+    if (parsed) {
+        /* Success; update cached location information */
+        update_lac_ci (self, lac, ci, cgreg ? 1 : 0);
 
-    /* Success; update cached location information */
-    update_lac_ci (self, lac, ci, cgreg ? 1 : 0);
-
-    /* Only update access technology if it appeared in the CREG/CGREG response */
-    if (act != -1)
-        mm_generic_gsm_update_access_technology (self, etsi_act_to_mm_act (act));
+        /* Only update access technology if it appeared in the CREG/CGREG response */
+        if (act != -1)
+            mm_generic_gsm_update_access_technology (self, etsi_act_to_mm_act (act));
 
-    /* Update cached registration status */
-    reg_status_updated (self, cgreg_to_reg_type (cgreg), status, NULL);
+        /* Update cached registration status */
+        reg_status_updated (self, cgreg_to_reg_type (cgreg), status, NULL);
+    }
 
-    return TRUE;
+    return parsed;
 }
 
 #define CS_ERROR_TAG "cs-error"
@@ -3619,9 +3618,13 @@ cid_range_read (MMAtSerialPort *port,
                 g_match_info_next (match_info, NULL);
             }
 
-            if (cid == 0)
+            if (cid == 0) {
                 /* Choose something */
                 cid = 1;
+            }
+
+            g_match_info_free (match_info);
+            g_regex_unref (r);
         }
     } else
         info->error = g_error_new_literal (MM_MODEM_ERROR,
diff --git a/src/mm-modem-helpers.c b/src/mm-modem-helpers.c
index f6a0ffa3..66c3fb64 100644
--- a/src/mm-modem-helpers.c
+++ b/src/mm-modem-helpers.c
@@ -125,10 +125,8 @@ mm_gsm_parse_scan_response (const char *reply, GError **error)
     /* If we didn't get any hits, try the pre-UMTS format match */
     if (!g_regex_match (r, reply, 0, &match_info)) {
         g_regex_unref (r);
-        if (match_info) {
-            g_match_info_free (match_info);
-            match_info = NULL;
-        }
+        g_match_info_free (match_info);
+        match_info = NULL;
 
         /* Pre-UMTS format doesn't include the cell access technology after
          * the numeric operator element.
@@ -778,8 +776,8 @@ mm_gsm_parse_cscs_support_response (const char *reply,
             g_match_info_next (match_info, NULL);
             success = TRUE;
         }
-        g_match_info_free (match_info);
     }
+    g_match_info_free (match_info);
     g_regex_unref (r);
 
     if (success)
@@ -1020,8 +1018,8 @@ mm_parse_cind_test_response (const char *reply, GError **error)
 
             g_match_info_next (match_info, NULL);
         }
-        g_match_info_free (match_info);
     }
+    g_match_info_free (match_info);
     g_regex_unref (r);
 
     return hash;
@@ -1086,11 +1084,10 @@ mm_parse_cind_query_response(const char *reply, GError **error)
         g_free (str);
         g_match_info_next (match_info, NULL);
     }
-    g_match_info_free (match_info);
 
 done:
-    if (r)
-        g_regex_unref (r);
+    g_match_info_free (match_info);
+    g_regex_unref (r);
 
     return array;
 }
diff --git a/src/mm-serial-parsers.c b/src/mm-serial-parsers.c
index 344e1bc7..f94e1156 100644
--- a/src/mm-serial-parsers.c
+++ b/src/mm-serial-parsers.c
@@ -125,8 +125,6 @@ mm_serial_parser_v0_parse (gpointer data,
         } else
             code = MM_MOBILE_ERROR_UNKNOWN;
 
-        g_match_info_free (match_info);
-
         switch (code) {
         case 0: /* OK */
             break;
@@ -155,9 +153,10 @@ mm_serial_parser_v0_parse (gpointer data,
         remove_matches (parser->generic_response, response);
     }
 
+    g_match_info_free (match_info);
+
     if (!found) {
         found = g_regex_match_full (parser->detailed_error, response->str, response->len, 0, 0, &match_info, NULL);
-
         if (found) {
             str = g_match_info_fetch (match_info, 1);
             if (str) {
@@ -166,9 +165,9 @@ mm_serial_parser_v0_parse (gpointer data,
             } else
                 code = MM_MOBILE_ERROR_UNKNOWN;
 
-            g_match_info_free (match_info);
             local_error = mm_mobile_error_for_code (code);
         }
+        g_match_info_free (match_info);
     }
 
     if (found)
@@ -260,7 +259,7 @@ mm_serial_parser_v1_parse (gpointer data,
     GMatchInfo *match_info;
     GError *local_error = NULL;
     gboolean found = FALSE;
-    char *str;
+    char *str = NULL;
     int code;
 
     g_return_val_if_fail (parser != NULL, FALSE);
@@ -306,10 +305,9 @@ mm_serial_parser_v1_parse (gpointer data,
             str = g_match_info_fetch (match_info, 1);
             g_assert (str);
             local_error = mm_mobile_error_for_code (atoi (str));
-            g_free (str);
-            g_match_info_free (match_info);
             goto done;
         }
+        g_match_info_free (match_info);
     }
 
     /* Numeric CME errors */
@@ -320,10 +318,9 @@ mm_serial_parser_v1_parse (gpointer data,
         str = g_match_info_fetch (match_info, 1);
         g_assert (str);
         local_error = mm_mobile_error_for_code (atoi (str));
-        g_free (str);
-        g_match_info_free (match_info);
         goto done;
     }
+    g_match_info_free (match_info);
 
     /* Numeric CMS errors */
     /* Todo
@@ -337,10 +334,9 @@ mm_serial_parser_v1_parse (gpointer data,
         str = g_match_info_fetch (match_info, 1);
         g_assert (str);
         local_error = mm_mobile_error_for_code (atoi (str));
-        g_free (str);
-        g_match_info_free (match_info);
         goto done;
     }
+    g_match_info_free (match_info);
 
     /* String CME errors */
     found = g_regex_match_full (parser->regex_cme_error_str,
@@ -350,10 +346,9 @@ mm_serial_parser_v1_parse (gpointer data,
         str = g_match_info_fetch (match_info, 1);
         g_assert (str);
         local_error = mm_mobile_error_for_string (str);
-        g_free (str);
-        g_match_info_free (match_info);
         goto done;
     }
+    g_match_info_free (match_info);
 
     /* Motorola EZX errors */
     found = g_regex_match_full (parser->regex_ezx_error,
@@ -363,19 +358,19 @@ mm_serial_parser_v1_parse (gpointer data,
         str = g_match_info_fetch (match_info, 1);
         g_assert (str);
         local_error = mm_mobile_error_for_code (MM_MOBILE_ERROR_UNKNOWN);
-        g_free (str);
-        g_match_info_free (match_info);
         goto done;
     }
+    g_match_info_free (match_info);
 
     /* Last resort; unknown error */
     found = g_regex_match_full (parser->regex_unknown_error,
                                 response->str, response->len,
-                                0, 0, NULL, NULL);
+                                0, 0, &match_info, NULL);
     if (found) {
         local_error = mm_mobile_error_for_code (MM_MOBILE_ERROR_UNKNOWN);
         goto done;
     }
+    g_match_info_free (match_info);
 
     /* Connection failures */
     found = g_regex_match_full (parser->regex_connect_failed,
@@ -398,13 +393,12 @@ mm_serial_parser_v1_parse (gpointer data,
             code = MM_MODEM_CONNECT_ERROR_NO_CARRIER;
         }
 
-        g_free (str);
-        g_match_info_free (match_info);
-
         local_error = mm_modem_connect_error_for_code (code);
     }
 
 done:
+    g_free (str);
+    g_match_info_free (match_info);
     if (found)
         response_clean (response);