diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2025-06-08 23:25:36 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2025-06-29 18:13:41 -0400 |
| commit | 05da054d43770e229dfb0e185c15452eed14364c (patch) | |
| tree | e99c8dd4d3e780ffe309be758bb5c53356f05c00 /fs/namespace.c | |
| parent | e031251cb249f824ad67cb0b2fc18b68d5792b8d (diff) | |
| download | random-05da054d43770e229dfb0e185c15452eed14364c.tar.gz | |
new predicate: anon_ns_root(mount)
checks if mount is the root of an anonymouns namespace.
Switch open-coded equivalents to using it.
For mounts that belong to anon namespace !mnt_has_parent(mount)
is the same as mount == ns->root, and intent is more obvious in
the latter form.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 28 |
1 files changed, 3 insertions, 25 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index c4feb83159785f..ea01fea2ac93ca 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2480,9 +2480,7 @@ struct vfsmount *clone_private_mount(const struct path *path) * loops get created. */ if (!check_mnt(old_mnt)) { - if (!is_mounted(&old_mnt->mnt) || - !is_anon_ns(old_mnt->mnt_ns) || - mnt_has_parent(old_mnt)) + if (!anon_ns_root(old_mnt)) return ERR_PTR(-EINVAL); if (!check_for_nsfs_mounts(old_mnt)) @@ -3649,9 +3647,6 @@ static int do_move_mount(struct path *old_path, ns = old->mnt_ns; err = -EINVAL; - /* The thing moved must be mounted... */ - if (!is_mounted(&old->mnt)) - goto out; if (check_mnt(old)) { /* if the source is in our namespace... */ @@ -3664,10 +3659,8 @@ static int do_move_mount(struct path *old_path, } else { /* * otherwise the source must be the root of some anon namespace. - * AV: check for mount being root of an anon namespace is worth - * an inlined predicate... */ - if (!is_anon_ns(ns) || mnt_has_parent(old)) + if (!anon_ns_root(old)) goto out; /* * Bail out early if the target is within the same namespace - @@ -5028,22 +5021,7 @@ static int do_mount_setattr(struct path *path, struct mount_kattr *kattr) err = -EINVAL; lock_mount_hash(); - /* Ensure that this isn't anything purely vfs internal. */ - if (!is_mounted(&mnt->mnt)) - goto out; - - /* - * If this is an attached mount make sure it's located in the callers - * mount namespace. If it's not don't let the caller interact with it. - * - * If this mount doesn't have a parent it's most often simply a - * detached mount with an anonymous mount namespace. IOW, something - * that's simply not attached yet. But there are apparently also users - * that do change mount properties on the rootfs itself. That obviously - * neither has a parent nor is it a detached mount so we cannot - * unconditionally check for detached mounts. - */ - if ((mnt_has_parent(mnt) || !is_anon_ns(mnt->mnt_ns)) && !check_mnt(mnt)) + if (!anon_ns_root(mnt) && !check_mnt(mnt)) goto out; /* |