From e7faaf3ea4be82540cacd21c4722f02d754fff44 Mon Sep 17 00:00:00 2001
From: Susan Hinrichs <shinrich@verizonmedia.com>
Date: Wed, 19 Aug 2020 22:15:11 +0000
Subject: [PATCH] Protect TSActionCancel from null INKContInternal actions

---
 src/traffic_server/InkAPI.cc | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/traffic_server/InkAPI.cc b/src/traffic_server/InkAPI.cc
index f5d8891f493..9dd2c3d5535 100644
--- a/src/traffic_server/InkAPI.cc
+++ b/src/traffic_server/InkAPI.cc
@@ -6820,11 +6820,20 @@ TSActionCancel(TSAction actionp)
   Action *thisaction;
   INKContInternal *i;
 
+  // Nothing to cancel
+  if (actionp == nullptr) {
+    return;
+  }
+
   /* This is a hack. Should be handled in ink_types */
   if ((uintptr_t)actionp & 0x1) {
     thisaction = (Action *)((uintptr_t)actionp - 1);
-    i          = (INKContInternal *)thisaction->continuation;
-    i->handle_event_count(EVENT_IMMEDIATE);
+    if (thisaction) {
+      i = (INKContInternal *)thisaction->continuation;
+      i->handle_event_count(EVENT_IMMEDIATE);
+    } else { // The action pointer for an INKContInternal was effectively null, just go away
+      return;
+    }
   } else {
     thisaction = (Action *)actionp;
   }