author: Linus Torvalds <torvalds@linux-foundation.org> 2017-05-12 11:39:59 -0700
committer: Linus Torvalds <torvalds@linux-foundation.org> 2017-05-12 11:39:59 -0700
commit: 050453295f808dd683b9a88f58a1b29540097394
parent: e0c4a5fc750e22c6f8d5c1ab7cc18592b88852ab
Commit Summary:
Diffstat:
1 file changed, 11 insertions, 7 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index b3b115bd4e1e..8bd3e4d448b9 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -3462,8 +3462,9 @@ static void mntns_put(struct ns_common *ns)
static int mntns_install(struct nsproxy *nsproxy, struct ns_common *ns)
{
struct fs_struct *fs = current->fs;
- struct mnt_namespace *mnt_ns = to_mnt_ns(ns);
+ struct mnt_namespace *mnt_ns = to_mnt_ns(ns), *old_mnt_ns;
struct path root;
+ int err;
if (!ns_capable(mnt_ns->user_ns, CAP_SYS_ADMIN) ||
!ns_capable(current_user_ns(), CAP_SYS_CHROOT) ||
@@ -3474,15 +3475,18 @@ static int mntns_install(struct nsproxy *nsproxy, struct ns_common *ns)
return -EINVAL;
get_mnt_ns(mnt_ns);
- put_mnt_ns(nsproxy->mnt_ns);
+ old_mnt_ns = nsproxy->mnt_ns;
nsproxy->mnt_ns = mnt_ns;
/* Find the root */
- root.mnt = &mnt_ns->root->mnt;
- root.dentry = mnt_ns->root->mnt.mnt_root;
- path_get(&root);
- while(d_mountpoint(root.dentry) && follow_down_one(&root))
- ;
+ err = vfs_path_lookup(mnt_ns->root->mnt.mnt_root, &mnt_ns->root->mnt,
+ "/", LOOKUP_DOWN, &root);
+ if (err) {
+ /* revert to old namespace */
+ nsproxy->mnt_ns = old_mnt_ns;
+ put_mnt_ns(mnt_ns);
+ return err;
+ }
/* Update the pwd and root */
set_fs_pwd(fs, &root);