1 files changed, 37 insertions, 18 deletions

diff --git a/networking/ifupdown.c b/networking/ifupdown.c
index 8170e80b3..818bec2d6 100644
--- a/networking/ifupdown.c
+++ b/networking/ifupdown.c
@@ -388,8 +388,8 @@ static int loopback_up6(struct interface_defn_t *ifd, execfn *exec)
 {
 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
         int result;
-        result = execute("ip link set %iface% up", ifd, exec);
-        result +=execute("ip addr add ::1 dev %iface% label %label%", ifd, exec);
+        result =execute("ip addr add ::1 dev %iface% label %label%", ifd, exec);
+        result += execute("ip link set %iface% up", ifd, exec);
         return( result);
 #else
         return( execute("ifconfig %iface% add ::1", ifd, exec));
@@ -409,8 +409,8 @@ static int static_up6(struct interface_defn_t *ifd, execfn *exec)
 {
         int result;
 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
-        result = execute("ip link set %iface% up", ifd, exec);
-        result += execute("ip addr add %address%/%netmask% dev %iface% label %label%", ifd, exec);
+        result = execute("ip addr add %address%/%netmask% dev %iface% label %label%", ifd, exec);
+        result += execute("ip link set %iface% up", ifd, exec);
         result += execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec);
 #else
         result = execute("ifconfig %iface% [[media %media%]] [[hw %hwaddress%]] [[mtu %mtu%]] up", ifd, exec);
@@ -435,8 +435,8 @@ static int v4tunnel_up(struct interface_defn_t *ifd, execfn *exec)
         int result;
         result = execute("ip tunnel add %iface% mode sit remote "
                                 "%endpoint% [[local %local%]] [[ttl %ttl%]]", ifd, exec);
-        result += execute("ip link set %iface% up", ifd, exec);
         result += execute("ip addr add %address%/%netmask% dev %iface% label %label%", ifd, exec);
+        result += execute("ip link set %iface% up", ifd, exec);
         result += execute("[[ ip route add ::/0 via %gateway% ]]", ifd, exec);
         return( result);
 }
@@ -467,8 +467,8 @@ static int loopback_up(struct interface_defn_t *ifd, execfn *exec)
 {
 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
         int result;
-        result = execute("ip link set %iface% up", ifd, exec);
-        result += execute("ip addr add 127.0.0.1/8 dev %iface% label %label%", ifd, exec);
+        result = execute("ip addr add 127.0.0.1/8 dev %iface% label %label%", ifd, exec);
+        result += execute("ip link set %iface% up", ifd, exec);
         return(result);
 #else
         return( execute("ifconfig %iface% 127.0.0.1 up", ifd, exec));
@@ -491,9 +491,9 @@ static int static_up(struct interface_defn_t *ifd, execfn *exec)
 {
         int result;
 #ifdef CONFIG_FEATURE_IFUPDOWN_IP
-        result = execute("ip link set %iface% up", ifd, exec);
-        result += execute("ip addr add %address%/%bnmask% [[broadcast %broadcast%]] "
+        result = execute("ip addr add %address%/%bnmask% [[broadcast %broadcast%]] "
                         "dev %iface% label %label%", ifd, exec);
+        result += execute("ip link set %iface% up", ifd, exec);
         result += execute("[[ ip route add default via %gateway% dev %iface% ]]", ifd, exec);
 #else
         result = execute("ifconfig %iface% %address% netmask %netmask% "
@@ -1116,38 +1116,57 @@ static int popen2(FILE **in, FILE **out, char *command, ...)
         /* unreached */
 }
 
-static char * run_mapping(char *physical, char *logical, int len, struct mapping_defn_t * map)
+static char * run_mapping(char *physical, struct mapping_defn_t * map)
 {
         FILE *in, *out;
         int i, status;
         pid_t pid;
 
-        char *new_logical = NULL;
+        char *logical = bb_xstrdup(physical);
 
+        /* Run the mapping script. */
         pid = popen2(&in, &out, map->script, physical, NULL);
-        if (pid == 0) {
-                return 0;
-        }
+
+        /* popen2() returns 0 on failure. */
+        if (pid == 0)
+                return logical;
+
+        /* Write mappings to stdin of mapping script. */
         for (i = 0; i < map->n_mappings; i++) {
                 fprintf(in, "%s\n", map->mapping[i]);
         }
         fclose(in);
         waitpid(pid, &status, 0);
+
         if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
-                new_logical = (char *)xmalloc(MAX_INTERFACE_LENGTH);
+                /* If the mapping script exited successfully, try to
+                 * grab a line of output and use that as the name of the
+                 * logical interface. */
+                char *new_logical = (char *)xmalloc(MAX_INTERFACE_LENGTH);
 
                 if (fgets(new_logical, MAX_INTERFACE_LENGTH, out)) {
+                        /* If we are able to read a line of output from the script,
+                         * remove any trailing whitespace and use this value
+                         * as the name of the logical interface. */
                         char *pch = new_logical + bb_strlen(new_logical) - 1;
 
                         while (pch >= new_logical && isspace(*pch))
                                 *(pch--) = '\0';
+
+                        free(logical);
+                        logical = new_logical;
+                } else {
+                        /* If we are UNABLE to read a line of output, discard are
+                         * freshly allocated memory. */
+                        free(new_logical);
                 }
         }
+
         fclose(out);
 
-        return new_logical ? new_logical : logical;
+        return logical;
 }
-#endif /* CONFIG_FEATURE_IFUPDOWN_IPV6 */
+#endif /* CONFIG_FEATURE_IFUPDOWN_MAPPING */
 
 static llist_t *find_iface_state(llist_t *state_list, const char *iface)
 {
@@ -1335,7 +1354,7 @@ extern int ifupdown_main(int argc, char **argv)
                                         if (verbose) {
                                                 printf("Running mapping script %s on %s\n", currmap->script, liface);
                                         }
-                                        liface = run_mapping(iface, liface, sizeof(liface), currmap);
+                                        liface = run_mapping(iface, currmap);
                                         break;
                                 }
                         }