When analyze use-after-free or double-free issue, recording the enqueuing work stacks is helpful to preserve usage history which potentially gives a hint about the affected code.
For workqueue it has turned out to be useful to record the enqueuing work call stacks. Because user can see KASAN report to determine whether it is root cause. They don't need to enable debugobjects, but they have a chance to find out the root cause. Signed-off-by: Walter Wu <[email protected]> Suggested-by: Marco Elver <[email protected]> Acked-by: Marco Elver <[email protected]> Acked-by: Tejun Heo <[email protected]> Reviewed-by: Dmitry Vyukov <[email protected]> Reviewed-by: Andrey Konovalov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Lai Jiangshan <[email protected]> --- v2: - Thanks for Marco suggestion. - Remove unnecessary code - reuse kasan_record_aux_stack() and aux_stack to record timer and workqueue stack --- kernel/workqueue.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index c41c3c17b86a..9dd65ac60d6e 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1324,6 +1324,9 @@ static void insert_work(struct pool_workqueue *pwq, struct work_struct *work, { struct worker_pool *pool = pwq->pool; + /* record the work call stack in order to print it in KASAN reports */ + kasan_record_aux_stack(work); + /* we own @work, set data and link */ set_work_pwq(work, pwq, extra_flags); list_add_tail(&work->entry, head); -- 2.18.0
