lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 21 Aug 2018 14:03:17 +0200 From: Johannes Berg <johannes@...solutions.net> To: Tejun Heo <tj@...nel.org>, Lai Jiangshan <jiangshanlai@...il.com> Cc: linux-kernel@...r.kernel.org, linux-wireless@...r.kernel.org, Johannes Berg <johannes.berg@...el.com> Subject: [PATCH 2/2] workqueue: create lockdep dependency in flush_work() From: Johannes Berg <johannes.berg@...el.com> In flush_work(), we need to create a lockdep dependency so that the following scenario is appropriately tagged as a problem: work_function() { mutex_lock(&mutex); ... } other_function() { mutex_lock(&mutex); flush_work(&work); // or cancel_work_sync(&work); } This is a problem since the work might be running and be blocked on trying to acquire the mutex. Signed-off-by: Johannes Berg <johannes.berg@...el.com> --- kernel/workqueue.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index a6c2b823f348..29d4d84ba512 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -2852,6 +2852,11 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr, might_sleep(); + if (!from_cancel) { + lock_map_acquire(&work->lockdep_map); + lock_map_release(&work->lockdep_map); + } + local_irq_disable(); pool = get_work_pool(work); if (!pool) { -- 2.14.4
Powered by blists - more mailing lists