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Date:   Fri, 16 Mar 2018 10:16:36 -0400 (EDT)
Message-Id: <20180316.101636.803564728843702383.davem@davemloft.net>
To:     mgamal@redhat.com
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        devel@linuxdriverproject.org, vkuznets@redhat.com,
        otubo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] hv_netvsc: Make sure out channel is fully opened on
 send
From:   David Miller <davem@davemloft.net>
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From: Mohammed Gamal <mgamal@redhat.com>
Date: Tue, 13 Mar 2018 20:06:50 +0100

> Dring high network traffic changes to network interface parameters
> such as number of channels or MTU can cause a kernel panic with a NULL
> pointer dereference. This is due to netvsc_device_remove() being
> called and deallocating the channel ring buffers, which can then be
> accessed by netvsc_send_pkt() before they're allocated on calling
> netvsc_device_add()
> 
> The patch fixes this problem by checking the channel state and returning
> ENODEV if not yet opened. We also move the call to hv_ringbuf_avail_percent()
> which may access the uninitialized ring buffer.
> 
> Signed-off-by: Mohammed Gamal <mgamal@redhat.com>

Based upon the discusion on this patch, it looks like this will be fixed
in some other way.