no rootfs => mounts are always relative to hosts /

All lxc.mount.entry entries will be relative to the hosts / when a container
does not specify a lxc.rootfs.

Signed-off-by: Christian Brauner <christian.brauner@mailbox.org>

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 41e9ef83dc50e83a93761f8ca2acde37de41b23a..39a86c776ba4a3fc1b01367ddd5e12ab0337ba1b 100644 (file)
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -1807,7 +1807,22 @@ static inline int mount_entry_on_generic(struct mntent *mntent,
 
 static inline int mount_entry_on_systemfs(struct mntent *mntent)
 {
-       return mount_entry_on_generic(mntent, mntent->mnt_dir, NULL, NULL, NULL);
+       char path[MAXPATHLEN];
+       int ret;
+
+       /* For containers created without a rootfs all mounts are treated as
+        * absolute paths starting at / on the host. */
+       if (mntent->mnt_dir[0] != '/')
+               ret = snprintf(path, sizeof(path), "/%s", mntent->mnt_dir);
+       else
+               ret = snprintf(path, sizeof(path), "%s", mntent->mnt_dir);
+
+       if (ret < 0 || ret >= sizeof(path)) {
+               ERROR("path name too long");
+               return -1;
+       }
+
+       return mount_entry_on_generic(mntent, path, NULL, NULL, NULL);
 }
 
 static int mount_entry_on_absolute_rootfs(struct mntent *mntent,
@@ -1868,7 +1883,7 @@ static int mount_entry_on_relative_rootfs(struct mntent *mntent,
 
        /* relative to root mount point */
        ret = snprintf(path, sizeof(path), "%s/%s", rootfs->mount, mntent->mnt_dir);
-       if (ret >= sizeof(path)) {
+       if (ret < 0 || ret >= sizeof(path)) {
                ERROR("path name too long");
                return -1;
        }