From: Eric Dumazet <eric.dumazet@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: netdev <netdev@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: strange crashes in tcp_poll() via epoll_wait
Date: Fri, 19 Jul 2013 09:24:17 -0700 [thread overview]
Message-ID: <1374251057.26476.17.camel@edumazet-glaptop> (raw)
Hi Al
I tried to debug strange crashes in tcp_poll() called from
sys_epoll_wait() -> sock_poll()
The symptom is that sock->sk is NULL and we therefore dereference a NULL
pointer.
It's really rare crashes but still, it would be nice to understand where
is the bug. Presumably latest kernels would crash in sock_poll() because
of the sk_can_busy_loop(sock->sk) call.
We do test sock->sk being NULL in sock_fasync(), but epoll should be
safe because of existing synchronization (epmutex) ?
Any idea?
Thanks !
next reply other threads:[~2013-07-19 16:24 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-19 16:24 Eric Dumazet [this message]
2013-07-19 23:50 ` strange crashes in tcp_poll() via epoll_wait Eric Wong
2013-07-20 0:10 ` Eric Dumazet
2013-07-20 2:03 ` Eric Wong
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