David Howells 63ad66d484 afs: Fix dynamic root lookup DNS check
[ Upstream commit 74cef6872ceaefb5b6c5c60641371ea28702d358 ]

In the afs dynamic root directory, the ->lookup() function does a DNS check
on the cell being asked for and if the DNS upcall reports an error it will
report an error back to userspace (typically ENOENT).

However, if a failed DNS upcall returns a new-style result, it will return
a valid result, with the status field set appropriately to indicate the
type of failure - and in that case, dns_query() doesn't return an error and
we let stat() complete with no error - which can cause confusion in
userspace as subsequent calls that trigger d_automount then fail with
ENOENT.

Fix this by checking the status result from a valid dns_query() and
returning an error if it indicates a failure.

Fixes: bbb4c4323a4d ("dns: Allow the dns resolver to retrieve a server set")
Reported-by: Markus Suvanto <markus.suvanto@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=216637
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-05 15:12:24 +01:00
..
2023-11-28 16:55:00 +00:00
2021-09-18 13:40:15 +02:00
2023-05-17 11:47:35 +02:00
2023-09-19 12:20:23 +02:00
2023-02-22 12:55:54 +01:00
2023-09-23 11:01:09 +02:00
2022-06-09 10:21:16 +02:00
2023-12-08 08:46:15 +01:00
2023-01-04 11:39:23 +01:00
2023-01-14 10:16:27 +01:00