Bug#655387: [PATCH] usb: cdc_ether: Ignore bogus union descriptor for RNDIS devices
2012/1/11 Bjørn Mork bj...@mork.no if you have the patience to test yet-another-patch. Bjørn Yes, I do, but: 2012/1/11 Oliver Neukum said: You are trying something subtle here. Stop doing that. Use a dedicated flag or a clearly named goto. All this is obviusly over my programming skills so, just tell me what to do and i'll do it. Iker
Bug#655387: Samsung galaxy S won't tether trough usb due to bad CDC descriptors
El 10 de enero de 2012 21:21, Jonathan Nieder jrnie...@gmail.com escribió: Iker Salmón San Millán wrote: This bug affects all kernels i've tried in debian wheezy, sid and experimental, I found a bug report in ubuntu where i found this patch that solves the problem, but the user who wrote the patch described it as workaroung instead of fix: Link, please. https://bugs.launchpad.net/ubuntu/+source/linux/+bug/796006 Also, could you describe the symptoms further? What steps would I perform to reproduce the bug if I had the hardware, what are the expected and actual results, and how does the difference indicate a bug? If you connect the samsung galaxy S (i know also SII is affected) to the usb hub and activate usb tethering it won't create usb0 interface and dmesg shows this: [ 509.033511] usb 2-2: USB disconnect, device number 5 [ 509.304059] usb 2-2: new high-speed USB device number 6 using ehci_hcd [ 509.438155] usb 2-2: New USB device found, idVendor=04e8, idProduct=6881 [ 509.438165] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 509.438172] usb 2-2: Product: SAMSUNG_Android [ 509.438178] usb 2-2: Manufacturer: SAMSUNG [ 509.438183] usb 2-2: SerialNumber: 353271BC9D8400EC [ 509.743606] usbcore: registered new interface driver cdc_ether [ 509.745205] usb 2-2: bad CDC descriptors [ 509.745231] usbcore: registered new interface driver rndis_host [ 509.753788] usb 2-2: bad CDC descriptors [ 509.753821] usbcore: registered new interface driver rndis_wlan If you apply the patch and rebuild the kernel the usb0 interface is created correctly when you activate usb tether. I don't know what else can i comment, surely there are people much more prepared than me to report this things, but i'll try my best if you ask me something or ask me tro try anything Thanks for your work, Jonathan No, Thanks for yours Iker
Bug#655387: [PATCH] usb: cdc_ether: Ignore bogus union descriptor for RNDIS devices
Sorry, but didn't work, same dmesg with bad cdc descriptors and usb0
interface is not created.
I tested with 3.2.0-rc7 kernel.
Regards, iker
2012/1/10 Bjørn Mork bj...@mork.no
Some RNDIS devices include a bogus CDC Union descriptor pointing
to non-existing interfaces. The RNDIS code is already prepared
to handle devices without a CDC Union descriptor, so we can just
ignore it.
Cc: Markus Kolb linux-201...@tower-net.de
Cc: Iker Salmón San Millán sha...@esdebian.org
Cc: Jonathan Nieder jrnie...@gmail.com
Cc: Oliver Neukum oli...@neukum.name
Cc: 655...@bugs.debian.org
Cc: sta...@vger.kernel.org
Signed-off-by: Bjørn Mork bj...@mork.no
---
How about this, which IMHO is less intrusive? Only build-tested, as I
don't have any of the failing devices, so it will obviously need
testing from anyone with such a device.
drivers/net/usb/cdc_ether.c | 10 +-
1 files changed, 9 insertions(+), 1 deletions(-)
diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index 41a61ef..2109f34 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -195,7 +195,15 @@ int usbnet_generic_cdc_bind(struct usbnet *dev,
struct usb_interface *intf)
info-control,
info-u-bSlaveInterface0,
info-data);
- goto bad_desc;
+ /* Fallback to guessing for rndis
+* class devices with bogus union
+* descriptor.
+* Fixes some Samsung Android devices
+*/
+ if (rndis)
+ info-u = NULL;
+ else
+ goto bad_desc;
}
if (info-control != intf) {
dev_dbg(intf-dev, bogus CDC Union\n);
--
1.7.7.3
