diff options
author | Aleksa Sarai <cyphar@cyphar.com> | 2019-12-07 01:13:26 +1100 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2019-12-08 19:09:36 -0500 |
commit | 2b98149c2377bff12be5dd3ce02ae0506e2dd613 (patch) | |
tree | 95fb705a14f99ab1b6ca600a529a66c8793f7dcc | |
parent | e42617b825f8073569da76dc4510bfa019b1c35a (diff) |
namei: only return -ECHILD from follow_dotdot_rcu()
It's over-zealous to return hard errors under RCU-walk here, given that
a REF-walk will be triggered for all other cases handling ".." under
RCU.
The original purpose of this check was to ensure that if a rename occurs
such that a directory is moved outside of the bind-mount which the
resolution started in, it would be detected and blocked to avoid being
able to mess with paths outside of the bind-mount. However, triggering a
new REF-walk is just as effective a solution.
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Fixes: 397d425dc26d ("vfs: Test for and handle paths that are unreachable from their mnt_root")
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r-- | fs/namei.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/namei.c b/fs/namei.c index d6c91d1e88cb..17ebaac2da49 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1365,7 +1365,7 @@ static int follow_dotdot_rcu(struct nameidata *nd) nd->path.dentry = parent; nd->seq = seq; if (unlikely(!path_connected(&nd->path))) - return -ENOENT; + return -ECHILD; break; } else { struct mount *mnt = real_mount(nd->path.mnt); |