<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/usb/gadget/function/u_ether.c, branch linux-6.2.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Revert "usb: gadget: u_ether: Do not make UDC parent of the net device"</title>
<updated>2023-02-09T12:18:24+00:00</updated>
<author>
<name>Paul Cercueil</name>
<email>paul@crapouillou.net</email>
</author>
<published>2023-02-09T10:56:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bb07bd68fa0983e3915f83c471382868860389fe'/>
<id>bb07bd68fa0983e3915f83c471382868860389fe</id>
<content type='text'>
This reverts commit 321b59870f850a10dbb211ecd2bd87b41497ea6f.

This commit broke USB networking on Ingenic SoCs and maybe elsewhere.
The actual reason is unknown; and while a proper fix would be better,
we're sitting at -rc7 now, so a revert is justified - and we can work on
re-introducing this change for 6.3.

Fixes: 321b59870f85 ("usb: gadget: u_ether: Do not make UDC parent of the net device")
Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Acked-by: Sascha Hauer &lt;s.hauer@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20230209105626.10597-1-paul@crapouillou.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reverts commit 321b59870f850a10dbb211ecd2bd87b41497ea6f.

This commit broke USB networking on Ingenic SoCs and maybe elsewhere.
The actual reason is unknown; and while a proper fix would be better,
we're sitting at -rc7 now, so a revert is justified - and we can work on
re-introducing this change for 6.3.

Fixes: 321b59870f85 ("usb: gadget: u_ether: Do not make UDC parent of the net device")
Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Acked-by: Sascha Hauer &lt;s.hauer@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20230209105626.10597-1-paul@crapouillou.net
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: Do not make UDC parent of the net device</title>
<updated>2022-11-09T11:39:33+00:00</updated>
<author>
<name>Sascha Hauer</name>
<email>s.hauer@pengutronix.de</email>
</author>
<published>2022-11-04T13:10:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=321b59870f850a10dbb211ecd2bd87b41497ea6f'/>
<id>321b59870f850a10dbb211ecd2bd87b41497ea6f</id>
<content type='text'>
The UDC is not a suitable parent of the net device as the UDC can
change or vanish during the lifecycle of the ethernet gadget. This
can be illustrated with the following:

mkdir -p /sys/kernel/config/usb_gadget/mygadget
cd /sys/kernel/config/usb_gadget/mygadget
mkdir -p configs/c.1/strings/0x409
echo "C1:Composite Device" &gt; configs/c.1/strings/0x409/configuration
mkdir -p functions/ecm.usb0
ln -s functions/ecm.usb0 configs/c.1/
echo "dummy_udc.0" &gt; UDC
rmmod dummy_hcd

The 'rmmod' removes the UDC from the just created gadget, leaving
the still existing net device with a no longer existing parent.

Accessing the ethernet device with commands like:

ip --details link show usb0

will result in a KASAN splat:

==================================================================
BUG: KASAN: use-after-free in if_nlmsg_size+0x3e8/0x528
Read of size 4 at addr c5c84754 by task ip/357

CPU: 3 PID: 357 Comm: ip Not tainted 6.1.0-rc3-00013-gd14953726b24-dirty #324
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
 unwind_backtrace from show_stack+0x10/0x14
 show_stack from dump_stack_lvl+0x58/0x70
 dump_stack_lvl from print_report+0x134/0x4d4
 print_report from kasan_report+0x78/0x10c
 kasan_report from if_nlmsg_size+0x3e8/0x528
 if_nlmsg_size from rtnl_getlink+0x2b4/0x4d0
 rtnl_getlink from rtnetlink_rcv_msg+0x1f4/0x674
 rtnetlink_rcv_msg from netlink_rcv_skb+0xb4/0x1f8
 netlink_rcv_skb from netlink_unicast+0x294/0x478
 netlink_unicast from netlink_sendmsg+0x328/0x640
 netlink_sendmsg from ____sys_sendmsg+0x2a4/0x3b4
 ____sys_sendmsg from ___sys_sendmsg+0xc8/0x12c
 ___sys_sendmsg from sys_sendmsg+0xa0/0x120
 sys_sendmsg from ret_fast_syscall+0x0/0x1c

Solve this by not setting the parent of the ethernet device.

Signed-off-by: Sascha Hauer &lt;s.hauer@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20221104131031.850850-2-s.hauer@pengutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The UDC is not a suitable parent of the net device as the UDC can
change or vanish during the lifecycle of the ethernet gadget. This
can be illustrated with the following:

mkdir -p /sys/kernel/config/usb_gadget/mygadget
cd /sys/kernel/config/usb_gadget/mygadget
mkdir -p configs/c.1/strings/0x409
echo "C1:Composite Device" &gt; configs/c.1/strings/0x409/configuration
mkdir -p functions/ecm.usb0
ln -s functions/ecm.usb0 configs/c.1/
echo "dummy_udc.0" &gt; UDC
rmmod dummy_hcd

The 'rmmod' removes the UDC from the just created gadget, leaving
the still existing net device with a no longer existing parent.

Accessing the ethernet device with commands like:

ip --details link show usb0

will result in a KASAN splat:

==================================================================
BUG: KASAN: use-after-free in if_nlmsg_size+0x3e8/0x528
Read of size 4 at addr c5c84754 by task ip/357

CPU: 3 PID: 357 Comm: ip Not tainted 6.1.0-rc3-00013-gd14953726b24-dirty #324
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
 unwind_backtrace from show_stack+0x10/0x14
 show_stack from dump_stack_lvl+0x58/0x70
 dump_stack_lvl from print_report+0x134/0x4d4
 print_report from kasan_report+0x78/0x10c
 kasan_report from if_nlmsg_size+0x3e8/0x528
 if_nlmsg_size from rtnl_getlink+0x2b4/0x4d0
 rtnl_getlink from rtnetlink_rcv_msg+0x1f4/0x674
 rtnetlink_rcv_msg from netlink_rcv_skb+0xb4/0x1f8
 netlink_rcv_skb from netlink_unicast+0x294/0x478
 netlink_unicast from netlink_sendmsg+0x328/0x640
 netlink_sendmsg from ____sys_sendmsg+0x2a4/0x3b4
 ____sys_sendmsg from ___sys_sendmsg+0xc8/0x12c
 ___sys_sendmsg from sys_sendmsg+0xa0/0x120
 sys_sendmsg from ret_fast_syscall+0x0/0x1c

Solve this by not setting the parent of the ethernet device.

Signed-off-by: Sascha Hauer &lt;s.hauer@pengutronix.de&gt;
Link: https://lore.kernel.org/r/20221104131031.850850-2-s.hauer@pengutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: move from strlcpy with unused retval to strscpy</title>
<updated>2022-08-19T09:08:54+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2022-08-18T21:01:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b7db5733a5ace9acc1f3104c9050c5aa1363f13b'/>
<id>b7db5733a5ace9acc1f3104c9050c5aa1363f13b</id>
<content type='text'>
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Reviewed-by: Richard Leitner &lt;richard.leitner@skidata.com&gt;
Reviewed-by: Laurent Pinchart &lt;laurent.pinchart+renesas@ideasonboard.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Link: https://lore.kernel.org/r/20220818210116.7517-1-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Reviewed-by: Richard Leitner &lt;richard.leitner@skidata.com&gt;
Reviewed-by: Laurent Pinchart &lt;laurent.pinchart+renesas@ideasonboard.com&gt;
Acked-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Link: https://lore.kernel.org/r/20220818210116.7517-1-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: Remove duplicated include in u_ether.c</title>
<updated>2022-06-24T11:42:17+00:00</updated>
<author>
<name>Yang Li</name>
<email>yang.lee@linux.alibaba.com</email>
</author>
<published>2022-06-23T01:08:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=508aeb54e4f0225f4ff3da9b7ec8ac44ce30aad8'/>
<id>508aeb54e4f0225f4ff3da9b7ec8ac44ce30aad8</id>
<content type='text'>
Fix following includecheck warning:
./drivers/usb/gadget/function/u_ether.c: linux/etherdevice.h is included
more than once.

Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/20220623010808.9816-1-yang.lee@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix following includecheck warning:
./drivers/usb/gadget/function/u_ether.c: linux/etherdevice.h is included
more than once.

Signed-off-by: Yang Li &lt;yang.lee@linux.alibaba.com&gt;
Link: https://lore.kernel.org/r/20220623010808.9816-1-yang.lee@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: fix regression in setting fixed MAC address</title>
<updated>2022-06-10T09:12:53+00:00</updated>
<author>
<name>Marian Postevca</name>
<email>posteuca@mutex.one</email>
</author>
<published>2022-06-03T15:34:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b337af3a4d6147000b7ca6b3438bf5c820849b37'/>
<id>b337af3a4d6147000b7ca6b3438bf5c820849b37</id>
<content type='text'>
In systemd systems setting a fixed MAC address through
the "dev_addr" module argument fails systematically.
When checking the MAC address after the interface is created
it always has the same but different MAC address to the one
supplied as argument.

This is partially caused by systemd which by default will
set an internally generated permanent MAC address for interfaces
that are marked as having a randomly generated address.

Commit 890d5b40908bfd1a ("usb: gadget: u_ether: fix race in
setting MAC address in setup phase") didn't take into account
the fact that the interface must be marked as having a set
MAC address when it's set as module argument.

Fixed by marking the interface with NET_ADDR_SET when
the "dev_addr" module argument is supplied.

Fixes: 890d5b40908bfd1a ("usb: gadget: u_ether: fix race in setting MAC address in setup phase")
Cc: stable@vger.kernel.org
Signed-off-by: Marian Postevca &lt;posteuca@mutex.one&gt;
Link: https://lore.kernel.org/r/20220603153459.32722-1-posteuca@mutex.one
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In systemd systems setting a fixed MAC address through
the "dev_addr" module argument fails systematically.
When checking the MAC address after the interface is created
it always has the same but different MAC address to the one
supplied as argument.

This is partially caused by systemd which by default will
set an internally generated permanent MAC address for interfaces
that are marked as having a randomly generated address.

Commit 890d5b40908bfd1a ("usb: gadget: u_ether: fix race in
setting MAC address in setup phase") didn't take into account
the fact that the interface must be marked as having a set
MAC address when it's set as module argument.

Fixed by marking the interface with NET_ADDR_SET when
the "dev_addr" module argument is supplied.

Fixes: 890d5b40908bfd1a ("usb: gadget: u_ether: fix race in setting MAC address in setup phase")
Cc: stable@vger.kernel.org
Signed-off-by: Marian Postevca &lt;posteuca@mutex.one&gt;
Link: https://lore.kernel.org/r/20220603153459.32722-1-posteuca@mutex.one
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: fix race in setting MAC address in setup phase</title>
<updated>2021-12-13T14:22:23+00:00</updated>
<author>
<name>Marian Postevca</name>
<email>posteuca@mutex.one</email>
</author>
<published>2021-12-04T21:49:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=890d5b40908bfd1a79be018d2d297cf9df60f4ee'/>
<id>890d5b40908bfd1a79be018d2d297cf9df60f4ee</id>
<content type='text'>
When listening for notifications through netlink of a new interface being
registered, sporadically, it is possible for the MAC to be read as zero.
The zero MAC address lasts a short period of time and then switches to a
valid random MAC address.

This causes problems for netd in Android, which assumes that the interface
is malfunctioning and will not use it.

In the good case we get this log:
InterfaceController::getCfg() ifName usb0
 hwAddr 92:a8:f0:73:79:5b ipv4Addr 0.0.0.0 flags 0x1002

In the error case we get these logs:
InterfaceController::getCfg() ifName usb0
 hwAddr 00:00:00:00:00:00 ipv4Addr 0.0.0.0 flags 0x1002

netd : interfaceGetCfg("usb0")
netd : interfaceSetCfg() -&gt; ServiceSpecificException
 (99, "[Cannot assign requested address] : ioctl() failed")

The reason for the issue is the order in which the interface is setup,
it is first registered through register_netdev() and after the MAC
address is set.

Fixed by first setting the MAC address of the net_device and after that
calling register_netdev().

Fixes: bcd4a1c40bee885e ("usb: gadget: u_ether: construct with default values and add setters/getters")
Cc: stable@vger.kernel.org
Signed-off-by: Marian Postevca &lt;posteuca@mutex.one&gt;
Link: https://lore.kernel.org/r/20211204214912.17627-1-posteuca@mutex.one
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When listening for notifications through netlink of a new interface being
registered, sporadically, it is possible for the MAC to be read as zero.
The zero MAC address lasts a short period of time and then switches to a
valid random MAC address.

This causes problems for netd in Android, which assumes that the interface
is malfunctioning and will not use it.

In the good case we get this log:
InterfaceController::getCfg() ifName usb0
 hwAddr 92:a8:f0:73:79:5b ipv4Addr 0.0.0.0 flags 0x1002

In the error case we get these logs:
InterfaceController::getCfg() ifName usb0
 hwAddr 00:00:00:00:00:00 ipv4Addr 0.0.0.0 flags 0x1002

netd : interfaceGetCfg("usb0")
netd : interfaceSetCfg() -&gt; ServiceSpecificException
 (99, "[Cannot assign requested address] : ioctl() failed")

The reason for the issue is the order in which the interface is setup,
it is first registered through register_netdev() and after the MAC
address is set.

Fixed by first setting the MAC address of the net_device and after that
calling register_netdev().

Fixes: bcd4a1c40bee885e ("usb: gadget: u_ether: construct with default values and add setters/getters")
Cc: stable@vger.kernel.org
Signed-off-by: Marian Postevca &lt;posteuca@mutex.one&gt;
Link: https://lore.kernel.org/r/20211204214912.17627-1-posteuca@mutex.one
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: use eth_hw_addr_set()</title>
<updated>2021-10-20T17:31:50+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2021-10-19T17:21:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=99984b081f99ca30bbbebe5490a8328b0a212931'/>
<id>99984b081f99ca30bbbebe5490a8328b0a212931</id>
<content type='text'>
Commit 406f42fa0d3c ("net-next: When a bond have a massive amount
of VLANs...") introduced a rbtree for faster Ethernet address look
up. To maintain netdev-&gt;dev_addr in this tree we need to make all
the writes to it got through appropriate helpers.

Reviewed-by: Maciej Żenczykowski &lt;maze@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Link: https://lore.kernel.org/r/20211019172124.1413620-1-kuba@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 406f42fa0d3c ("net-next: When a bond have a massive amount
of VLANs...") introduced a rbtree for faster Ethernet address look
up. To maintain netdev-&gt;dev_addr in this tree we need to make all
the writes to it got through appropriate helpers.

Reviewed-by: Maciej Żenczykowski &lt;maze@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Link: https://lore.kernel.org/r/20211019172124.1413620-1-kuba@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: fix a potential null pointer dereference</title>
<updated>2021-07-21T08:04:19+00:00</updated>
<author>
<name>Maciej Żenczykowski</name>
<email>maze@google.com</email>
</author>
<published>2021-07-01T11:48:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8ae01239609b29ec2eff55967c8e0fe3650cfa09'/>
<id>8ae01239609b29ec2eff55967c8e0fe3650cfa09</id>
<content type='text'>
f_ncm tx timeout can call us with null skb to flush
a pending frame.  In this case skb is NULL to begin
with but ceases to be null after dev-&gt;wrap() completes.

In such a case in-&gt;maxpacket will be read, even though
we've failed to check that 'in' is not NULL.

Though I've never observed this fail in practice,
however the 'flush operation' simply does not make sense with
a null usb IN endpoint - there's nowhere to flush to...
(note that we're the gadget/device, and IN is from the point
 of view of the host, so here IN actually means outbound...)

Cc: Brooke Basile &lt;brookebasile@gmail.com&gt;
Cc: "Bryan O'Donoghue" &lt;bryan.odonoghue@linaro.org&gt;
Cc: Felipe Balbi &lt;balbi@kernel.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Lorenzo Colitti &lt;lorenzo@google.com&gt;
Signed-off-by: Maciej Żenczykowski &lt;maze@google.com&gt;
Link: https://lore.kernel.org/r/20210701114834.884597-6-zenczykowski@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
f_ncm tx timeout can call us with null skb to flush
a pending frame.  In this case skb is NULL to begin
with but ceases to be null after dev-&gt;wrap() completes.

In such a case in-&gt;maxpacket will be read, even though
we've failed to check that 'in' is not NULL.

Though I've never observed this fail in practice,
however the 'flush operation' simply does not make sense with
a null usb IN endpoint - there's nowhere to flush to...
(note that we're the gadget/device, and IN is from the point
 of view of the host, so here IN actually means outbound...)

Cc: Brooke Basile &lt;brookebasile@gmail.com&gt;
Cc: "Bryan O'Donoghue" &lt;bryan.odonoghue@linaro.org&gt;
Cc: Felipe Balbi &lt;balbi@kernel.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Lorenzo Colitti &lt;lorenzo@google.com&gt;
Signed-off-by: Maciej Żenczykowski &lt;maze@google.com&gt;
Link: https://lore.kernel.org/r/20210701114834.884597-6-zenczykowski@gmail.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: support configuring interface names.</title>
<updated>2021-01-15T15:08:53+00:00</updated>
<author>
<name>Lorenzo Colitti</name>
<email>lorenzo@google.com</email>
</author>
<published>2021-01-13T23:42:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=63d152149b2d0860ccf8c4e6596b6175b2b7ace6'/>
<id>63d152149b2d0860ccf8c4e6596b6175b2b7ace6</id>
<content type='text'>
This patch allows the administrator to configure the interface
name of a function using u_ether (e.g., eem, ncm, rndis).

Currently, all such interfaces, regardless of function type, are
always called usb0, usb1, etc. This makes it very cumbersome to
use more than one such type at a time, because userspace cannnot
easily tell the interfaces apart and apply the right
configuration to each one. Interface renaming in userspace based
on driver doesn't help, because the interfaces all have the same
driver. Without this patch, doing this require hacks/workarounds
such as setting fixed MAC addresses on the functions, and then
renaming by MAC address, or scraping configfs after each
interface is created to find out what it is.

Setting the interface name is done by writing to the same
"ifname" configfs attribute that reports the interface name after
the function is bound. The write must contain an interface
pattern such as "usb%d" (which will cause the net core to pick
the next available interface name starting with "usb").
This patch does not allow writing an exact interface name (as
opposed to a pattern) because if the interface already exists at
bind time, the bind will fail and the whole gadget will fail to
activate. This could be allowed in a future patch.

For compatibility with current userspace, when reading an ifname
that has not currently been set, the result is still "(unnamed
net_device)". Once a write to ifname happens, then reading ifname
will return whatever was last written.

Tested by configuring an rndis function and an ncm function on
the same gadget, and writing "rndis%d" to ifname on the rndis
function and "ncm%d" to ifname on the ncm function. When the
gadget was bound, the rndis interface was rndis0 and the ncm
interface was ncm0.

Signed-off-by: Lorenzo Colitti &lt;lorenzo@google.com&gt;
Link: https://lore.kernel.org/r/20210113234222.3272933-1-lorenzo@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch allows the administrator to configure the interface
name of a function using u_ether (e.g., eem, ncm, rndis).

Currently, all such interfaces, regardless of function type, are
always called usb0, usb1, etc. This makes it very cumbersome to
use more than one such type at a time, because userspace cannnot
easily tell the interfaces apart and apply the right
configuration to each one. Interface renaming in userspace based
on driver doesn't help, because the interfaces all have the same
driver. Without this patch, doing this require hacks/workarounds
such as setting fixed MAC addresses on the functions, and then
renaming by MAC address, or scraping configfs after each
interface is created to find out what it is.

Setting the interface name is done by writing to the same
"ifname" configfs attribute that reports the interface name after
the function is bound. The write must contain an interface
pattern such as "usb%d" (which will cause the net core to pick
the next available interface name starting with "usb").
This patch does not allow writing an exact interface name (as
opposed to a pattern) because if the interface already exists at
bind time, the bind will fail and the whole gadget will fail to
activate. This could be allowed in a future patch.

For compatibility with current userspace, when reading an ifname
that has not currently been set, the result is still "(unnamed
net_device)". Once a write to ifname happens, then reading ifname
will return whatever was last written.

Tested by configuring an rndis function and an ncm function on
the same gadget, and writing "rndis%d" to ifname on the rndis
function and "ncm%d" to ifname on the ncm function. When the
gadget was bound, the rndis interface was rndis0 and the ncm
interface was ncm0.

Signed-off-by: Lorenzo Colitti &lt;lorenzo@google.com&gt;
Link: https://lore.kernel.org/r/20210113234222.3272933-1-lorenzo@google.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: gadget: u_ether: Fix MTU size mismatch with RX packet size</title>
<updated>2020-12-28T14:45:51+00:00</updated>
<author>
<name>Manish Narani</name>
<email>manish.narani@xilinx.com</email>
</author>
<published>2020-11-17T07:13:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0a88fa221ce911c331bf700d2214c5b2f77414d3'/>
<id>0a88fa221ce911c331bf700d2214c5b2f77414d3</id>
<content type='text'>
Fix the MTU size issue with RX packet size as the host sends the packet
with extra bytes containing ethernet header. This causes failure when
user sets the MTU size to the maximum i.e. 15412. In this case the
ethernet packet received will be of length 15412 plus the ethernet header
length. This patch fixes the issue where there is a check that RX packet
length must not be more than max packet length.

Fixes: bba787a860fa ("usb: gadget: ether: Allow jumbo frames")
Signed-off-by: Manish Narani &lt;manish.narani@xilinx.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/1605597215-122027-1-git-send-email-manish.narani@xilinx.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix the MTU size issue with RX packet size as the host sends the packet
with extra bytes containing ethernet header. This causes failure when
user sets the MTU size to the maximum i.e. 15412. In this case the
ethernet packet received will be of length 15412 plus the ethernet header
length. This patch fixes the issue where there is a check that RX packet
length must not be more than max packet length.

Fixes: bba787a860fa ("usb: gadget: ether: Allow jumbo frames")
Signed-off-by: Manish Narani &lt;manish.narani@xilinx.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Link: https://lore.kernel.org/r/1605597215-122027-1-git-send-email-manish.narani@xilinx.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
