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Date:   Sat, 21 Nov 2020 14:03:11 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Yves-Alexis Perez <corsac@corsac.net>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Martin Habets <mhabets@solarflare.com>,
        Luc Van Oostenryck <luc.vanoostenryck@gmail.com>,
        Shannon Nelson <snelson@pensando.io>,
        "Michael S. Tsirkin" <mst@redhat.com>, linux-usb@vger.kernel.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Matti Vuorela <matti.vuorela@bitfactor.fi>,
        stable@vger.kernel.org
Subject: Re: [PATCH] usbnet: ipheth: fix connectivity with iOS 14
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In-Reply-To: <20201119172439.94988-1-corsac@corsac.net>
References: <CAAn0qaXmysJ9vx3ZEMkViv_B19ju-_ExN8Yn_uSefxpjS6g4Lw@mail.gmail.com>
        <20201119172439.94988-1-corsac@corsac.net>
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On Thu, 19 Nov 2020 18:24:39 +0100 Yves-Alexis Perez wrote:
> Starting with iOS 14 released in September 2020, connectivity using the
> personal hotspot USB tethering function of iOS devices is broken.
> 
> Communication between the host and the device (for example ICMP traffic
> or DNS resolution using the DNS service running in the device itself)
> works fine, but communication to endpoints further away doesn't work.
> 
> Investigation on the matter shows that UDP and ICMP traffic from the
> tethered host is reaching the Internet at all. For TCP traffic there are
> exchanges between tethered host and server but packets are modified in
> transit leading to impossible communication.
> 
> After some trials Matti Vuorela discovered that reducing the URB buffer
> size by two bytes restored the previous behavior. While a better
> solution might exist to fix the issue, since the protocol is not
> publicly documented and considering the small size of the fix, let's do
> that.
> 
> Tested-by: Matti Vuorela <matti.vuorela@bitfactor.fi>
> Signed-off-by: Yves-Alexis Perez <corsac@corsac.net>
> Link: https://lore.kernel.org/linux-usb/CAAn0qaXmysJ9vx3ZEMkViv_B19ju-_ExN8Yn_uSefxpjS6g4Lw@mail.gmail.com/
> Link: https://github.com/libimobiledevice/libimobiledevice/issues/1038

Applied to net with the typo fixed, thanks!