apparmor/kernel-patches/2.6.26/d_namespace_path.diff

59 lines
1.8 KiB
Diff

From: Andreas Gruenbacher <agruen@suse.de>
Subject: Add d_namespace_path() to compute namespace relative pathnames
In AppArmor, we are interested in pathnames relative to the namespace root.
This is the same as d_path() except for the root where the search ends. Add
a function for computing the namespace-relative path.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: John Johansen <jjohansen@suse.de>
---
fs/namespace.c | 29 +++++++++++++++++++++++++++++
include/linux/mount.h | 2 ++
2 files changed, 31 insertions(+)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2351,3 +2351,32 @@ void __put_mnt_ns(struct mnt_namespace *
release_mounts(&umount_list);
kfree(ns);
}
+
+char *d_namespace_path(struct dentry *dentry, struct vfsmount *vfsmnt,
+ char *buf, int buflen)
+{
+ struct path root, ns_root = { };
+ struct path path = { .mnt = vfsmnt, .dentry = dentry };
+ char *res;
+
+ read_lock(&current->fs->lock);
+ root = current->fs->root;
+ path_get(&current->fs->root);
+ read_unlock(&current->fs->lock);
+ spin_lock(&vfsmount_lock);
+ if (root.mnt)
+ ns_root.mnt = mntget(root.mnt->mnt_ns->root);
+ if (ns_root.mnt)
+ ns_root.dentry = dget(ns_root.mnt->mnt_root);
+ spin_unlock(&vfsmount_lock);
+ res = __d_path(&path, &ns_root, buf, buflen,
+ D_PATH_FAIL_DELETED | D_PATH_DISCONNECT);
+ path_put(&root);
+ path_put(&ns_root);
+
+ /* Prevent empty path for lazily unmounted filesystems. */
+ if (!IS_ERR(res) && *res == '\0')
+ *--res = '.';
+ return res;
+}
+EXPORT_SYMBOL(d_namespace_path);
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -113,4 +113,6 @@ extern void mark_mounts_for_expiry(struc
extern spinlock_t vfsmount_lock;
extern dev_t name_to_dev_t(char *name);
+extern char *d_namespace_path(struct dentry *, struct vfsmount *, char *, int);
+
#endif /* _LINUX_MOUNT_H */