rename physical nics at shutdown

When a physical nic is being set up, store its ifindex and original name
in struct lxc_conf.  At reboot, reset the original name.
We can't just go over the original network list in lxc_conf at shutdown
because that may be tweaked in the meantime through the C api.  The
saved_nics list is only setup during lxc_spawn(), and restored and
freed after lxc_start.

Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1086244

Changelog: remove non-effect change in execute.c

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 79d96d70fc124860308657a1660626c93a1676de..45e0b31dae17e80691b8defa8a09b712c22eb1ff 100644 (file)
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -1821,6 +1821,21 @@ static int setup_network(struct lxc_list *network)
        return 0;
 }
 
+void lxc_rename_phys_nics_on_shutdown(struct lxc_conf *conf)
+{
+       int i;
+
+       INFO("running to reset %d nic names", conf->num_savednics);
+       for (i=0; i<conf->num_savednics; i++) {
+               struct saved_nic *s = &conf->saved_nics[i];
+               INFO("resetting nic %d to %s\n", s->ifindex, s->orig_name);
+               lxc_netdev_rename_by_index(s->ifindex, s->orig_name);
+               free(s->orig_name);
+       }
+       conf->num_savednics = 0;
+       free(conf->saved_nics);
+}
+
 static int setup_private_host_hw_addr(char *veth1)
 {
        struct ifreq ifr;
@@ -2710,6 +2725,18 @@ int lxc_clear_hooks(struct lxc_conf *c, const char *key)
        return 0;
 }
 
+void lxc_clear_saved_nics(struct lxc_conf *conf)
+{
+       int i;
+
+       if (!conf->num_savednics)
+               return;
+       for (i=0; i < conf->num_savednics; i++)
+               free(conf->saved_nics[i].orig_name);
+       conf->saved_nics = 0;
+       free(conf->saved_nics);
+}
+
 void lxc_conf_free(struct lxc_conf *conf)
 {
        if (!conf)
@@ -2737,5 +2764,6 @@ void lxc_conf_free(struct lxc_conf *conf)
        lxc_clear_cgroups(conf, "lxc.cgroup");
        lxc_clear_hooks(conf, "lxc.hook");
        lxc_clear_mount_entries(conf);
+       lxc_clear_saved_nics(conf);
        free(conf);
 }

diff --git a/src/lxc/conf.h b/src/lxc/conf.h
index 694bce48e78a6c9d95a24b23879e6f34e5626d6f..3f6181f32b738a4de9e1dd81dd91d5dc376dd1d8 100644 (file)
--- a/src/lxc/conf.h
+++ b/src/lxc/conf.h
@@ -211,6 +211,11 @@ enum lxchooks {
        LXCHOOK_POSTSTOP, NUM_LXC_HOOKS};
 extern char *lxchook_names[NUM_LXC_HOOKS];
 
+struct saved_nic {
+       int ifindex;
+       char *orig_name;
+};
+
 struct lxc_conf {
        char *fstab;
        int tty;
@@ -221,6 +226,8 @@ struct lxc_conf {
        struct utsname *utsname;
        struct lxc_list cgroup;
        struct lxc_list network;
+       struct saved_nic *saved_nics;
+       int num_savednics;
        struct lxc_list mount_list;
        struct lxc_list caps;
        struct lxc_tty_info tty_info;
@@ -273,4 +280,6 @@ extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
  */
 
 extern int lxc_setup(const char *name, struct lxc_conf *lxc_conf);
+
+extern void lxc_rename_phys_nics_on_shutdown(struct lxc_conf *conf);
 #endif

diff --git a/src/lxc/execute.c b/src/lxc/execute.c
index 487765ff9d3547f527b61c21ad96706fb3272489..99800d08490108bebb44e0ecbc84335b45cadb51 100644 (file)
--- a/src/lxc/execute.c
+++ b/src/lxc/execute.c
@@ -27,7 +27,6 @@
 #include <unistd.h>
 #include <stdlib.h>
 
-
 #include "log.h"
 #include "start.h"
 

diff --git a/src/lxc/start.c b/src/lxc/start.c
index 3e26b27bea2b07e95ef8e28b9abb14fee285ec4c..7320d74a8665f09638f308027f570c47ed617642 100644 (file)
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -579,6 +579,37 @@ out_warn_father:
        return -1;
 }
 
+int save_phys_nics(struct lxc_conf *conf)
+{
+       struct lxc_list *iterator;
+
+       lxc_list_for_each(iterator, &conf->network) {
+               struct lxc_netdev *netdev = iterator->elem;
+
+               if (netdev->type != LXC_NET_PHYS)
+                       continue;
+               conf->saved_nics = realloc(conf->saved_nics,
+                               (conf->num_savednics+1)*sizeof(struct saved_nic));
+               if (!conf->saved_nics) {
+                       SYSERROR("failed to allocate memory");
+                       return -1;
+               }
+               conf->saved_nics[conf->num_savednics].ifindex = netdev->ifindex;
+               conf->saved_nics[conf->num_savednics].orig_name = strdup(netdev->link);
+               if (!conf->saved_nics[conf->num_savednics].orig_name) {
+                       SYSERROR("failed to allocate memory");
+                       return -1;
+               }
+               INFO("stored saved_nic #%d idx %d name %s\n", conf->num_savednics,
+                       conf->saved_nics[conf->num_savednics].ifindex,
+                       conf->saved_nics[conf->num_savednics].orig_name);
+               conf->num_savednics++;
+       }
+
+       return 0;
+}
+
+
 int lxc_spawn(struct lxc_handler *handler)
 {
        int failed_before_rename = 0;
@@ -613,6 +644,11 @@ int lxc_spawn(struct lxc_handler *handler)
                }
        }
 
+       if (save_phys_nics(handler->conf)) {
+               ERROR("failed to save physical nic info");
+               goto out_abort;
+       }
+
        /*
         * if the rootfs is not a blockdev, prevent the container from
         * marking it readonly.
@@ -739,6 +775,8 @@ int __lxc_start(const char *name, struct lxc_conf *conf,
                }
         }
 
+       lxc_rename_phys_nics_on_shutdown(handler->conf);
+
        err =  lxc_error_set_and_log(handler->pid, status);
 out_fini:
        lxc_delete_network(handler);