Since the task_is_descendant() function is used in YAMA and in audit,
pull the function into kernel/core/sched.c
Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
---
include/linux/sched.h | 3 +++
kernel/audit.c | 33 ---------------------------------
kernel/sched/core.c | 33 +++++++++++++++++++++++++++++++++
security/yama/yama_lsm.c | 33 ---------------------------------
4 files changed, 36 insertions(+), 66 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index a936d162513a..b251f018f4db 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1988,4 +1988,7 @@ static inline void rseq_syscall(struct pt_regs *regs)
const struct cpumask *sched_trace_rd_span(struct root_domain *rd);
+extern int task_is_descendant(struct task_struct *parent,
+ struct task_struct *child);
+
#endif
diff --git a/kernel/audit.c b/kernel/audit.c
index 69fe1e9af7cb..4fe7678304dd 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -2560,39 +2560,6 @@ static struct task_struct *audit_cont_owner(struct task_struct *tsk)
}
/*
- * task_is_descendant - walk up a process family tree looking for a match
- * @parent: the process to compare against while walking up from child
- * @child: the process to start from while looking upwards for parent
- *
- * Returns 1 if child is a descendant of parent, 0 if not.
- */
-static int task_is_descendant(struct task_struct *parent,
- struct task_struct *child)
-{
- int rc = 0;
- struct task_struct *walker = child;
-
- if (!parent || !child)
- return 0;
-
- rcu_read_lock();
- if (!thread_group_leader(parent))
- parent = rcu_dereference(parent->group_leader);
- while (walker->pid > 0) {
- if (!thread_group_leader(walker))
- walker = rcu_dereference(walker->group_leader);
- if (walker == parent) {
- rc = 1;
- break;
- }
- walker = rcu_dereference(walker->real_parent);
- }
- rcu_read_unlock();
-
- return rc;
-}
-
-/*
* audit_set_contid - set current task's audit contid
* @task: target task
* @contid: contid value
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2b037f195473..7ba9e07381fa 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7509,6 +7509,39 @@ void dump_cpu_task(int cpu)
}
/*
+ * task_is_descendant - walk up a process family tree looking for a match
+ * @parent: the process to compare against while walking up from child
+ * @child: the process to start from while looking upwards for parent
+ *
+ * Returns 1 if child is a descendant of parent, 0 if not.
+ */
+int task_is_descendant(struct task_struct *parent,
+ struct task_struct *child)
+{
+ int rc = 0;
+ struct task_struct *walker = child;
+
+ if (!parent || !child)
+ return 0;
+
+ rcu_read_lock();
+ if (!thread_group_leader(parent))
+ parent = rcu_dereference(parent->group_leader);
+ while (walker->pid > 0) {
+ if (!thread_group_leader(walker))
+ walker = rcu_dereference(walker->group_leader);
+ if (walker == parent) {
+ rc = 1;
+ break;
+ }
+ walker = rcu_dereference(walker->real_parent);
+ }
+ rcu_read_unlock();
+
+ return rc;
+}
+
+/*
* Nice levels are multiplicative, with a gentle 10% change for every
* nice level changed. I.e. when a CPU-bound task goes from nice 0 to
* nice 1, it will get ~10% less CPU time than another CPU-bound task
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index 94dc346370b1..25eae205eae8 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -263,39 +263,6 @@ static int yama_task_prctl(int option, unsigned long arg2, unsigned long arg3,
}
/**
- * task_is_descendant - walk up a process family tree looking for a match
- * @parent: the process to compare against while walking up from child
- * @child: the process to start from while looking upwards for parent
- *
- * Returns 1 if child is a descendant of parent, 0 if not.
- */
-static int task_is_descendant(struct task_struct *parent,
- struct task_struct *child)
-{
- int rc = 0;
- struct task_struct *walker = child;
-
- if (!parent || !child)
- return 0;
-
- rcu_read_lock();
- if (!thread_group_leader(parent))
- parent = rcu_dereference(parent->group_leader);
- while (walker->pid > 0) {
- if (!thread_group_leader(walker))
- walker = rcu_dereference(walker->group_leader);
- if (walker == parent) {
- rc = 1;
- break;
- }
- walker = rcu_dereference(walker->real_parent);
- }
- rcu_read_unlock();
-
- return rc;
-}
-
-/**
* ptracer_exception_found - tracer registered as exception for this tracee
* @tracer: the task_struct of the process attempting ptrace
* @tracee: the task_struct of the process to be ptraced
--
1.8.3.1
