Re: [PATCH] sunrpc: on successful gss error pipe write, don't return error (try #2)

[Trond Myklebust <trond.myklebust@fys.uio.no>]

On Fri, 2009-12-18 at 15:38 -0500, Jeff Layton wrote:

> Well, I'd like to think that we'd always get the lower layers right, but
> I know better :). We probably ought to code defensively here and account
> for the possibility that this function could return a different error
> due to an inadvertent change in a lower function.
> 
> If the "bad" error is transient then -EAGAIN would probably just paper
> over it. If it's not transient then the mount would hang. -EACCES is a
> nice hard error, but could be confused with a "real" -EACCES. We could
> BUG() in that case if we're sure it'd be a real bug...


switch (err) {
case -EACCES:
gss_msg->msg.errno = -EACCES;
break;
case -EFAULT:
case -ENOMEM:
case -EINVAL:
case -ENOSYS:
gss_msg->msg.errno = -EAGAIN;
break;
default:
BUG();
}

Yup. That looks good to me... ..and with the fixes to
gss_import_sec_context_kerberos and gss_import_sec_context, it will
actually be correct too.

BTW: get_key() returns EINVAL on error, so that does indeed need to be
supported in the above list.

Trond