From 1fc10f15eeac5a7e2efbf01dc4a8b0ca6ec0e8e0 Mon Sep 17 00:00:00 2001
From: Benjamin Berg <bberg@redhat.com>
Date: Thu, 10 Dec 2020 15:37:45 +0100
Subject: [PATCH] pam: Stop authorization if we couldn't parse signals

This really should never ever happen. If it does, don't continue but
stop instead.
---
 pam/pam_fprintd.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pam/pam_fprintd.c b/pam/pam_fprintd.c
index 51918b8..021f168 100644
--- a/pam/pam_fprintd.c
+++ b/pam/pam_fprintd.c
@@ -208,6 +208,7 @@ verify_result (sd_bus_message *m,
   if ((r = sd_bus_message_read (m, "sb", &result, &done)) < 0)
     {
       pam_syslog (data->pamh, LOG_ERR, "Failed to parse VerifyResult signal: %d", r);
+      data->verify_ret = PAM_AUTHINFO_UNAVAIL;
       return 0;
     }
 
@@ -255,6 +256,7 @@ verify_finger_selected (sd_bus_message *m,
   if (sd_bus_message_read_basic (m, 's', &finger_name) < 0)
     {
       pam_syslog (data->pamh, LOG_ERR, "Failed to parse VerifyFingerSelected signal: %d", errno);
+      data->verify_ret = PAM_AUTHINFO_UNAVAIL;
       return 0;
     }
 
@@ -630,6 +632,7 @@ name_owner_changed (sd_bus_message *m,
   if (sd_bus_message_read (m, "sss", &name, &old_owner, &new_owner) < 0)
     {
       pam_syslog (data->pamh, LOG_ERR, "Failed to parse NameOwnerChanged signal: %d", errno);
+      data->verify_ret = PAM_AUTHINFO_UNAVAIL;
       return 0;
     }