Re: [PATCH] sctp: relese sctp_stream_priorities at sctp_stream_outq_migrate()

[Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>]

On Wed, Nov 23, 2022 at 07:36:00PM +0900, Tetsuo Handa wrote:
> syzbot is reporting memory leak on sctp_stream_priorities [1], for
> sctp_stream_outq_migrate() is resetting SCTP_SO(stream, i)->ext to NULL
> without clearing SCTP_SO(new, i)->ext->prio_head list allocated by
> sctp_sched_prio_new_head(). Since sctp_sched_prio_free() is too late to
> clear if stream->outcnt was already shrunk or SCTP_SO(stream, i)->ext
> was already NULL, add a callback for clearing that list before shrinking
> stream->outcnt and/or resetting SCTP_SO(stream, i)->ext.
> 
> Link: https://syzkaller.appspot.com/bug?exrid=29c402e56c4760763cc0 [1]
> Reported-by: syzbot <syzbot+29c402e56c4760763cc0@syzkaller.appspotmail.com>
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> ---
> I can observe that the reproducer no longer reports memory leak. But
> is this change correct and sufficient? Are there similar locations?

Thanks, but please see my email from yesterday. This is on the right
way but a cleanup then is possible:
https://lore.kernel.org/linux-sctp/Y31ct%2FlSXNTm9ev9@t14s.localdomain/

  Marcelo