libmount: support for namespaces for helpers

Signed-off-by: Vaclav Dolezal <vdolezal@redhat.com>

diff --git a/libmount/src/context_mount.c b/libmount/src/context_mount.c
index 9245d73dd7fed93ac07fba4d44283c518f8f2494..5723958116dc9fdd1ebf09c161ee040acbb81b98 100644 (file)
--- a/libmount/src/context_mount.c
+++ b/libmount/src/context_mount.c
@@ -578,6 +578,10 @@ int mnt_context_mount_setopt(struct libmnt_context *cxt, int c, char *arg)
                if (arg)
                        rc = mnt_context_set_fstype(cxt, arg);
                break;
+       case 'N':
+               if (arg)
+                       rc = mnt_context_set_target_ns(cxt, arg);
+               break;
        default:
                return 1;
        }
@@ -587,7 +591,8 @@ int mnt_context_mount_setopt(struct libmnt_context *cxt, int c, char *arg)
 
 static int exec_helper(struct libmnt_context *cxt)
 {
-       char *o = NULL;
+       char *o = NULL, *namespace = NULL;
+       struct libmnt_ns *ns_tgt = mnt_context_get_target_ns(cxt);
        int rc;
        pid_t pid;
 
@@ -602,13 +607,20 @@ static int exec_helper(struct libmnt_context *cxt)
        if (rc)
                return -EINVAL;
 
+       if (ns_tgt->fd != -1
+           && asprintf(&namespace, "/proc/%i/fd/%i",
+                       getpid(), ns_tgt->fd) == -1) {
+               free(o);
+               return -ENOMEM;
+       }
+
        DBG_FLUSH;
 
        pid = fork();
        switch (pid) {
        case 0:
        {
-               const char *args[12], *type;
+               const char *args[14], *type;
                int i = 0;
 
                if (setgid(getgid()) < 0)
@@ -641,7 +653,11 @@ static int exec_helper(struct libmnt_context *cxt)
                        args[i++] = "-t";               /* 10 */
                        args[i++] = type;               /* 11 */
                }
-               args[i] = NULL;                         /* 12 */
+               if (namespace) {
+                       args[i++] = "-N";               /* 11 */
+                       args[i++] = namespace;          /* 12 */
+               }
+               args[i] = NULL;                         /* 13 */
                for (i = 0; args[i]; i++)
                        DBG(CXT, ul_debugobj(cxt, "argv[%d] = \"%s\"",
                                                        i, args[i]));

diff --git a/libmount/src/context_umount.c b/libmount/src/context_umount.c
index 3e320bec941ee0b0fa9668f89700a9a46d934a8e..70628b6cb6c4ae9dd862e43cee33647385b67193 100644 (file)
--- a/libmount/src/context_umount.c
+++ b/libmount/src/context_umount.c
@@ -520,6 +520,8 @@ eperm:
 
 static int exec_helper(struct libmnt_context *cxt)
 {
+       char *namespace = NULL;
+       struct libmnt_ns *ns_tgt = mnt_context_get_target_ns(cxt);
        int rc;
        pid_t pid;
 
@@ -535,13 +537,19 @@ static int exec_helper(struct libmnt_context *cxt)
                return rc;
        }
 
+       if (ns_tgt->fd != -1
+           && asprintf(&namespace, "/proc/%i/fd/%i",
+                       getpid(), ns_tgt->fd) == -1) {
+               return -ENOMEM;
+       }
+
        DBG_FLUSH;
 
        pid = fork();
        switch (pid) {
        case 0:
        {
-               const char *args[10], *type;
+               const char *args[12], *type;
                int i = 0;
 
                if (setgid(getgid()) < 0)
@@ -571,8 +579,12 @@ static int exec_helper(struct libmnt_context *cxt)
                        args[i++] = "-t";                       /* 8 */
                        args[i++] = (char *) type;              /* 9 */
                }
+               if (namespace) {
+                       args[i++] = "-N";                       /* 10 */
+                       args[i++] = namespace;                  /* 11 */
+               }
 
-               args[i] = NULL;                                 /* 10 */
+               args[i] = NULL;                                 /* 12 */
                for (i = 0; args[i]; i++)
                        DBG(CXT, ul_debugobj(cxt, "argv[%d] = \"%s\"",
                                                        i, args[i]));
@@ -643,6 +655,10 @@ int mnt_context_umount_setopt(struct libmnt_context *cxt, int c, char *arg)
                if (arg)
                        rc = mnt_context_set_fstype(cxt, arg);
                break;
+       case 'N':
+               if (arg)
+                       rc = mnt_context_set_target_ns(cxt, arg);
+               break;
        default:
                return 1;
        }