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: Fri, 20 Nov 2020 06:45:50 -0800 From: "Paul E. McKenney" <paulmck@...nel.org> To: Dmitry Vyukov <dvyukov@...gle.com> Cc: "Zhang, Qiang" <qiang.zhang@...driver.com>, Josh Triplett <josh@...htriplett.org>, Steven Rostedt <rostedt@...dmis.org>, Joel Fernandes <joel@...lfernandes.org>, rcu@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>, kasan-dev <kasan-dev@...glegroups.com>, Uladzislau Rezki <urezki@...il.com> Subject: Re: [PATCH] rcu: kasan: record and print kvfree_call_rcu call stack On Fri, Nov 20, 2020 at 06:34:40AM -0800, Paul E. McKenney wrote: > On Fri, Nov 20, 2020 at 09:51:15AM +0100, Dmitry Vyukov wrote: > > On Thu, Nov 19, 2020 at 10:49 PM Paul E. McKenney <paulmck@...nel.org> wrote: > > > > > > On Wed, Nov 18, 2020 at 11:53:09AM +0800, qiang.zhang@...driver.com wrote: > > > > From: Zqiang <qiang.zhang@...driver.com> > > > > > > > > Add kasan_record_aux_stack function for kvfree_call_rcu function to > > > > record call stacks. > > > > > > > > Signed-off-by: Zqiang <qiang.zhang@...driver.com> > > > > > > Thank you, but this does not apply on the "dev" branch of the -rcu tree. > > > See file:///home/git/kernel.org/rcutodo.html for more info. > > > > > > Adding others on CC who might have feedback on the general approach. > > > > > > Thanx, Paul > > > > > > > --- > > > > kernel/rcu/tree.c | 2 +- > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > > > > index da3414522285..a252b2f0208d 100644 > > > > --- a/kernel/rcu/tree.c > > > > +++ b/kernel/rcu/tree.c > > > > @@ -3506,7 +3506,7 @@ void kvfree_call_rcu(struct rcu_head *head, rcu_callback_t func) > > > > success = true; > > > > goto unlock_return; > > > > } > > > > - > > > > + kasan_record_aux_stack(ptr); > > > > success = kvfree_call_rcu_add_ptr_to_bulk(krcp, ptr); > > > > if (!success) { > > > > run_page_cache_worker(krcp); > > > > kvfree_call_rcu is intended to free objects, right? If so this is: > > True, but mightn't there still be RCU readers referencing this object for > some time, as in up to the point that the RCU grace period ends? If so, > won't adding this cause KASAN to incorrectly complain about those readers? > > Or am I missing something here? For example, is kasan_record_aux_stack() -only- recording the stack and not at all updating the allocated/freed state? Thanx, Paul > > Acked-by: Dmitry Vyukov <dvyukov@...gle.com>
Powered by blists - more mailing lists