Re: [BUG] signal: sighand unprotected when accessed by /proc

From: Oleg Nesterov
Date: Tue Jun 03 2014 - 16:11:04 EST


Steven, I am already sleeping, probably I just need to re-read your
email tomorrow, but...

On 06/03, Steven Rostedt wrote:
>
> When we convert the spin_lock into a rtmutex, when we hit the lock and
> it was contended (the task was in the process of exiting and it takes
> the lock to set tsk->sighand to NULL), instead of spinning, the task
> adds itself to the lock->wait_list and goes to sleep.

This is clear,

> Now, if that lock is released and reused (I didn't trace other tasks
> allocating these locks), it reinitializes the lock->wait_list.

How? From where? This should be done by sighand_ctor() only?

Oleg.

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