This is a note to let you know that I've just added the patch titled
net: qmi_wwan: fix divide by 0 on bad descriptors
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-qmi_wwan-fix-divide-by-0-on-bad-descriptors.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Sun Nov 19 11:12:05 CET 2017
From: Bjørn Mork <bjorn@xxxxxxx>
Date: Mon, 6 Nov 2017 15:32:18 +0100
Subject: net: qmi_wwan: fix divide by 0 on bad descriptors
From: Bjørn Mork <bjorn@xxxxxxx>
commit 7fd078337201cf7468f53c3d9ef81ff78cb6df3b upstream.
A CDC Ethernet functional descriptor with wMaxSegmentSize = 0 will
cause a divide error in usbnet_probe:
divide error: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc8-44453-g1fdc1a82c34f #56
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: usb_hub_wq hub_event
task: ffff88006bef5c00 task.stack: ffff88006bf60000
RIP: 0010:usbnet_update_max_qlen+0x24d/0x390 drivers/net/usb/usbnet.c:355
RSP: 0018:ffff88006bf67508 EFLAGS: 00010246
RAX: 00000000000163c8 RBX: ffff8800621fce40 RCX: ffff8800621fcf34
RDX: 0000000000000000 RSI: ffffffff837ecb7a RDI: ffff8800621fcf34
RBP: ffff88006bf67520 R08: ffff88006bef5c00 R09: ffffed000c43f881
R10: ffffed000c43f880 R11: ffff8800621fc406 R12: 0000000000000003
R13: ffffffff85c71de0 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88006ca00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe9c0d6dac CR3: 00000000614f4000 CR4: 00000000000006f0
Call Trace:
usbnet_probe+0x18b5/0x2790 drivers/net/usb/usbnet.c:1783
qmi_wwan_probe+0x133/0x220 drivers/net/usb/qmi_wwan.c:1338
usb_probe_interface+0x324/0x940 drivers/usb/core/driver.c:361
really_probe drivers/base/dd.c:413
driver_probe_device+0x522/0x740 drivers/base/dd.c:557
Fix by simply ignoring the bogus descriptor, as it is optional
for QMI devices anyway.
Fixes: 423ce8caab7e ("net: usb: qmi_wwan: New driver for Huawei QMI based WWAN devices")
Reported-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Signed-off-by: Bjørn Mork <bjorn@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/usb/qmi_wwan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -262,7 +262,7 @@ static int qmi_wwan_bind(struct usbnet *
}
/* errors aren't fatal - we can live with the dynamic address */
- if (cdc_ether) {
+ if (cdc_ether && cdc_ether->wMaxSegmentSize) {
dev->hard_mtu = le16_to_cpu(cdc_ether->wMaxSegmentSize);
usbnet_get_ethernet_addr(dev, cdc_ether->iMACAddress);
}
Patches currently in stable-queue which might be from bjorn@xxxxxxx are
queue-4.4/net-cdc_ether-fix-divide-by-0-on-bad-descriptors.patch
queue-4.4/net-qmi_wwan-fix-divide-by-0-on-bad-descriptors.patch