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From: subashab@codeaurora.org
To: netdev@vger.kernel.org
Cc: eric.dumazet@gmail.com
Subject: [RFC] Handling device free after a packet is passed to the network stack
Date: Fri, 27 Mar 2015 19:57:34 -0000	[thread overview]
Message-ID: <f3c7672edb978d520f12d72cb41d1e4d.squirrel@www.codeaurora.org> (raw)

We have been coming across a couple of scenarios where the device is freed
and the corresponding packets which were already queued up the stack
encounter crashes when they find that contents of skb->dev are no longer
valid.

Specifically, we have observed an instance where a cpu hotplug occurs
along with the network driver module unloading. When the packets are being
queued up the stack using netif_rx_ni from dev_cpu_callback, get_rps_cpus
crashes as it encounters invalid data at skb->dev since it would have been
freed.

We would like to know if the kernel provides some mechanisms to safeguard
against such scenarios.

--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux
Foundation Collaborative Project

             reply	other threads:[~2015-03-27 19:57 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-27 19:57 subashab [this message]
2015-03-28  2:49 ` [RFC] Handling device free after a packet is passed to the network stack Eric Dumazet
2015-03-30 14:19   ` Harout Hedeshian
2015-03-30 22:41     ` Eric Dumazet

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