[PATCH ghak90 V7 15/21] sched: pull task_is_descendant into kernel/sched/core.c
From: Richard Guy Briggs <hidden>
Date: 2019-09-19 01:26:52
Also in:
linux-fsdevel, lkml, netdev, netfilter-devel
Subsystem:
audit subsystem, scheduler, security subsystem, the rest, yama security module · Maintainers:
Paul Moore, Eric Paris, Ingo Molnar, Peter Zijlstra, Juri Lelli, Vincent Guittot, James Morris, "Serge E. Hallyn", Linus Torvalds, Kees Cook
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 <redacted> --- 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
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1.8.3.1