[gvfs/wip/oholy/smb-einval] smb: Ignore EINVAL for kerberos/ccache login

[Ondrej Holy <oholy src gnome org>]

commit c1e6c93fe8926ab52f2392dd0ff3cdc19ea07db0
Author: Ondrej Holy <oholy redhat com>
Date:   Mon Apr 11 10:54:04 2022 +0200

    smb: Ignore EINVAL for kerberos/ccache login
    
    With samba 4.16.0, mount operation fails with the "Invalid Argument" error
    when kerberos/ccache is misconfigured. Ignore this error, so user get a chance
    to login using the password.
    
    Fixes: https://gitlab.gnome.org/GNOME/gvfs/-/issues/611

 daemon/gvfsbackendsmb.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/daemon/gvfsbackendsmb.c b/daemon/gvfsbackendsmb.c
index 33d1a209..dbb167f6 100644
--- a/daemon/gvfsbackendsmb.c
+++ b/daemon/gvfsbackendsmb.c
@@ -513,7 +513,13 @@ do_mount (GVfsBackend *backend,
       if (res == 0)
         break;
 
-      if (op_backend->mount_cancelled || (errsv != EACCES && errsv != EPERM))
+      if (errsv == EINVAL && (op_backend->mount_try <= 1 && op_backend->user == NULL))
+        {
+          /* EINVAL is "expected" when kerberos/ccache is misconfigured, see:
+           * https://gitlab.gnome.org/GNOME/gvfs/-/issues/611
+           */
+        }
+      else if (op_backend->mount_cancelled || (errsv != EACCES && errsv != EPERM))
         {
           g_debug ("do_mount - (errno != EPERM && errno != EACCES), cancelled = %d, breaking\n", 
op_backend->mount_cancelled);
           break;