From 6dfd9fe54dfd615eb1dcb6a1281f3b5fddef190c Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 26 Feb 2020 12:33:48 -0500 Subject: follow_dotdot{,_rcu}(): switch to use of step_into() gets the regular mount crossing on result of .. Signed-off-by: Al Viro --- fs/namei.c | 31 +++++++------------------------ 1 file changed, 7 insertions(+), 24 deletions(-) (limited to 'fs') diff --git a/fs/namei.c b/fs/namei.c index 1749e435edc7..9c775013368a 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1722,33 +1722,18 @@ static const char *follow_dotdot_rcu(struct nameidata *nd) /* we know that mountpoint was pinned */ nd->path.dentry = mountpoint; nd->path.mnt = &mparent->mnt; - inode = inode2; + inode = nd->inode = inode2; nd->seq = seq; } } if (unlikely(!parent)) { if (unlikely(nd->flags & LOOKUP_BENEATH)) return ERR_PTR(-ECHILD); + return step_into(nd, WALK_NOFOLLOW, + nd->path.dentry, nd->inode, nd->seq); } else { - nd->path.dentry = parent; - nd->seq = seq; + return step_into(nd, WALK_NOFOLLOW, parent, inode, 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) @@ -1774,13 +1759,11 @@ static const char *follow_dotdot(struct nameidata *nd) if (unlikely(!parent)) { if (unlikely(nd->flags & LOOKUP_BENEATH)) return ERR_PTR(-EXDEV); + return step_into(nd, WALK_NOFOLLOW, + dget(nd->path.dentry), nd->inode, nd->seq); } else { - dput(nd->path.dentry); - nd->path.dentry = parent; + return step_into(nd, WALK_NOFOLLOW, parent, parent->d_inode, 0); } - follow_mount(&nd->path); - nd->inode = nd->path.dentry->d_inode; - return NULL; } static const char *handle_dots(struct nameidata *nd, int type) -- cgit v1.2.3