From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net V2] xen-netback: disable rogue vif in kthread
 context
Date: Wed, 26 Mar 2014 16:44:47 -0400 (EDT)
Message-ID: <20140326.164447.416212657407875997.davem@davemloft.net>
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=46rom: Wei Liu <wei.liu2@citrix.com>
Date: Tue, 25 Mar 2014 12:20:51 +0000

> When netback discovers frontend is sending malformed packet it will
> disables the interface which serves that frontend.
>=20
> However disabling a network interface involving taking a mutex which
> cannot be done in softirq context, so we need to defer this process t=
o
> kthread context.
>=20
> This patch does the following:
> 1. introduce a flag to indicate the interface is disabled.
> 2. check that flag in TX path, don't do any work if it's true.
> 3. check that flag in RX path, turn off that interface if it's true.
>=20
> The reason to disable it in RX path is because RX uses kthread. After
> this change the behavior of netback is still consistent -- it won't d=
o
> any TX work for a rogue frontend, and the interface will be eventuall=
y
> turned off.
>=20
> Also change a "continue" to "break" after xenvif_fatal_tx_err, as it
> doesn't make sense to continue processing packets if frontend is rogu=
e.
>=20
> This is a fix for XSA-90.
>=20
> Reported-by: T=F6r=F6k Edwin <edwin@etorok.net>
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>

What is the status of this patch?