Re: [PATCH 1/3] autofs - fix AT_NO_AUTOMOUNT not being honored

From: Ian Kent
Date: Wed Aug 09 2017 - 22:16:14 EST


On 09/08/17 17:51, Ian Kent wrote:
> On 09/08/17 16:39, David Howells wrote:
>> Ian Kent <raven@xxxxxxxxxx> wrote:
>>
>>> In order to handle the AT_NO_AUTOMOUNT for both system calls the
>>> negative dentry case in follow_automount() needs to be changed to
>>> return ENOENT when the LOOKUP_AUTOMOUNT flag is clear (and the other
>>> required flags are clear).
>>
>> Should the be EREMOTE instead of ENOENT?
>
> I thought about that and ended up thinking ENOENT was more sensible
> but I'll look at it again.

I think EREMOTE and ENOENT both are inaccurate.

There's no way to know if the negative dentry corresponds to a valid map
key, and we've seen increasing lookups from userspace applications for
invalid directories, so I'm not sure.

I went with ENOENT but I guess we could use EREMOTE, what's your thinking
on why EREMOTE might be better than ENOENT?

Ian