From b2fafaba35f490947b78e8d0d4f4264a137e64cd Mon Sep 17 00:00:00 2001 From: Chris Redpath Date: Fri, 10 Jan 2014 10:34:08 +0000 Subject: [PATCH] sched: hmp: Fix potential task_struct memory leak We use get_task_struct to increment the ref count on a task_struct so that even if the task dies with a pending migration we are still able to read the memory without causing a fault. In the case of non-running tasks, we forgot to decrement the ref count when we are done with the task. Signed-off-by: Chris Redpath Signed-off-by: Jon Medhurst --- kernel/sched/fair.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d89f4a8ddf41..43857fec77be 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -7027,13 +7027,13 @@ static void hmp_migrate_runnable_task(struct rq *rq) * with the source rq. */ if (src_rq->active_balance) - return; + goto out; if (src_rq->nr_running <= 1) - return; + goto out; if (task_rq(p) != src_rq) - return; + goto out; /* * Not sure if this applies here but one can never * be too cautious @@ -7068,6 +7068,8 @@ static void hmp_migrate_runnable_task(struct rq *rq) rcu_read_unlock(); double_unlock_balance(src_rq, dst_rq); +out: + put_task_struct(p); } static DEFINE_SPINLOCK(hmp_force_migration); -- 2.34.1