1 files changed, 6 insertions, 2 deletions

diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index dd4d36067c50..573723843a04 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -84,7 +84,7 @@ static void yama_ptracer_del(struct task_struct *tracer,
         spin_lock_bh(&ptracer_relations_lock);
         list_for_each_entry_safe(relation, safe, &ptracer_relations, node)
                 if (relation->tracee == tracee ||
-                    relation->tracer == tracer) {
+                    (tracer && relation->tracer == tracer)) {
                         list_del(&relation->node);
                         kfree(relation);
                 }
@@ -138,6 +138,8 @@ static int yama_task_prctl(int option, unsigned long arg2, unsigned long arg3,
                 if (arg2 == 0) {
                         yama_ptracer_del(NULL, myself);
                         rc = 0;
+                } else if (arg2 == PR_SET_PTRACER_ANY) {
+                        rc = yama_ptracer_add(NULL, myself);
                 } else {
                         struct task_struct *tracer;
 
@@ -208,6 +210,7 @@ static int ptracer_exception_found(struct task_struct *tracer,
         int rc = 0;
         struct ptrace_relation *relation;
         struct task_struct *parent = NULL;
+        bool found = false;
 
         spin_lock_bh(&ptracer_relations_lock);
         rcu_read_lock();
@@ -216,10 +219,11 @@ static int ptracer_exception_found(struct task_struct *tracer,
         list_for_each_entry(relation, &ptracer_relations, node)
                 if (relation->tracee == tracee) {
                         parent = relation->tracer;
+                        found = true;
                         break;
                 }
 
-        if (task_is_descendant(parent, tracer))
+        if (found && (parent == NULL || task_is_descendant(parent, tracer)))
                 rc = 1;
         rcu_read_unlock();
         spin_unlock_bh(&ptracer_relations_lock);