follow_dotdot{,_rcu}(): switch to use of step_into()

gets the regular mount crossing on result of ..

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2020-02-26 12:33:48 -05:00
parent 7521f22b3c
commit 6dfd9fe54d

View File

@ -1722,33 +1722,18 @@ static const char *follow_dotdot_rcu(struct nameidata *nd)
/* we know that mountpoint was pinned */ /* we know that mountpoint was pinned */
nd->path.dentry = mountpoint; nd->path.dentry = mountpoint;
nd->path.mnt = &mparent->mnt; nd->path.mnt = &mparent->mnt;
inode = inode2; inode = nd->inode = inode2;
nd->seq = seq; nd->seq = seq;
} }
} }
if (unlikely(!parent)) { if (unlikely(!parent)) {
if (unlikely(nd->flags & LOOKUP_BENEATH)) if (unlikely(nd->flags & LOOKUP_BENEATH))
return ERR_PTR(-ECHILD); return ERR_PTR(-ECHILD);
return step_into(nd, WALK_NOFOLLOW,
nd->path.dentry, nd->inode, nd->seq);
} else { } else {
nd->path.dentry = parent; return step_into(nd, WALK_NOFOLLOW, parent, inode, seq);
nd->seq = seq;
} }
while (unlikely(d_mountpoint(nd->path.dentry))) {
struct mount *mounted;
mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry);
if (unlikely(read_seqretry(&mount_lock, nd->m_seq)))
return ERR_PTR(-ECHILD);
if (!mounted)
break;
if (unlikely(nd->flags & LOOKUP_NO_XDEV))
return ERR_PTR(-ECHILD);
nd->path.mnt = &mounted->mnt;
nd->path.dentry = mounted->mnt.mnt_root;
inode = nd->path.dentry->d_inode;
nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);
}
nd->inode = inode;
return NULL;
} }
static const char *follow_dotdot(struct nameidata *nd) static const char *follow_dotdot(struct nameidata *nd)
@ -1774,13 +1759,11 @@ static const char *follow_dotdot(struct nameidata *nd)
if (unlikely(!parent)) { if (unlikely(!parent)) {
if (unlikely(nd->flags & LOOKUP_BENEATH)) if (unlikely(nd->flags & LOOKUP_BENEATH))
return ERR_PTR(-EXDEV); return ERR_PTR(-EXDEV);
return step_into(nd, WALK_NOFOLLOW,
dget(nd->path.dentry), nd->inode, nd->seq);
} else { } else {
dput(nd->path.dentry); return step_into(nd, WALK_NOFOLLOW, parent, parent->d_inode, 0);
nd->path.dentry = parent;
} }
follow_mount(&nd->path);
nd->inode = nd->path.dentry->d_inode;
return NULL;
} }
static const char *handle_dots(struct nameidata *nd, int type) static const char *handle_dots(struct nameidata *nd, int type)