https://bugzilla.redhat.com/show_bug.cgi?id=1374126
Due to how the processing for authentication using polkit works, the
virshConnect code must first "attempt" an virConnectOpenAuth and then
check for a "special" return error code VIR_ERR_AUTH_UNAVAILABLE in
order to attempt to "retry" the authentication after performing a creation
of a pkttyagent to handle the challenge/response for the client.
However, attempting to use a remote connection, (such as perhaps
"qemu+ssh://someuser@localhost/system"), will cause a never ending
loop since attempting to generate a pkttyagent would fail for the
network client connection resulting in a never ending loop since the
return code is always VIR_ERR_AUTH_UNAVAILABLE from virPolkitCheckAuth.
The only way out of the loop is a forced quit (e.g. ctrl-c) as the
@authfail wouldn't be incremented as a result of a failed authn from
pkttyagent.
So rather than take any extra step for which the only result will be
a failure, let's check if there is a URI and if it's not using ":///",
then just fail.
This resolves the never ending loop and will generate an error:
error: failed to connect to the hypervisor
error: authentication unavailable: no polkit agent available to authenticate action
'org.libvirt.unix.manage'
NB: If the authentication was for a sufficiently privileged client, such as
qemu+ssh://root@localhost/system, then the remoteDispatchAuthList "allows"
the authentication to use libvirt since @callerUid would be 0.
Signed-off-by: John Ferlan <jferlan(a)redhat.com>
---
tools/virsh.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/tools/virsh.c b/tools/virsh.c
index 1f5c2b1..be368ba 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -166,6 +166,11 @@ virshConnect(vshControl *ctl, const char *uri, bool readonly)
if (readonly)
goto cleanup;
+ /* No URI or indication of a requesting a remote connection, then
+ * polkit will not work for the authentication/authorization */
+ if (!uri || !(strstr(uri, ":///")))
+ goto cleanup;
But we can get here even without polkit, right? Therefore it'd be much
more safer to check err && err->domain == VIR_FROM_POLKIT.
Michal