[RFC PATCH v2 3/4] Connect rlimit-events with process life cycle

From: Krzysztof Opasiak
Date: Thu Dec 14 2017 - 17:01:25 EST


Add rlimit-events call to process lifecycle to ensure that
we get notified whenever process dies (to cleanup our watch
levels) or forks (to implement watch levels inheritance).

Signed-off-by: Krzysztof Opasiak <k.opasiak@xxxxxxxxxxx>
---
kernel/exit.c | 3 +++
kernel/fork.c | 11 ++++++++++-
2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/kernel/exit.c b/kernel/exit.c
index f6cad39f35df..d3b9e1b854a3 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -62,6 +62,7 @@
#include <linux/random.h>
#include <linux/rcuwait.h>
#include <linux/compat.h>
+#include <linux/rlimit_noti.h>

#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -846,6 +847,8 @@ void __noreturn do_exit(long code)
tty_audit_exit();
audit_free(tsk);

+ rlimit_noti_task_exit(tsk);
+
tsk->exit_code = code;
taskstats_exit(tsk, group_dead);

diff --git a/kernel/fork.c b/kernel/fork.c
index e54684b63c08..77bbac0bdfe9 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -100,6 +100,8 @@

#include <trace/events/sched.h>

+#include <linux/rlimit_noti.h>
+
#define CREATE_TRACE_POINTS
#include <trace/events/task.h>

@@ -1389,6 +1391,7 @@ static inline void posix_cpu_timers_init_group(struct signal_struct *sig) { }
static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
{
struct signal_struct *sig;
+ int ret;

if (clone_flags & CLONE_THREAD)
return 0;
@@ -1419,9 +1422,15 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
#endif

task_lock(current->group_leader);
- memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim);
+ memcpy(sig->rlim, current->signal->rlim, sizeof(sig->rlim));
task_unlock(current->group_leader);

+ ret = rlimit_noti_task_fork(current->group_leader, tsk);
+ if (ret) {
+ kmem_cache_free(signal_cachep, sig);
+ return ret;
+ }
+
posix_cpu_timers_init_group(sig);

tty_audit_fork(sig);
--
2.9.3