diff options
author | Bjørn Mork <bjorn@mork.no> | 2017-11-06 17:32:18 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-11-08 07:42:43 +0300 |
commit | 7fd078337201cf7468f53c3d9ef81ff78cb6df3b (patch) | |
tree | 4fb79589af21b0a4591f8902be6460f81343d09d | |
parent | 2cb80187ba065d7decad7c6614e35e07aec8a974 (diff) | |
download | linux-7fd078337201cf7468f53c3d9ef81ff78cb6df3b.tar.xz |
net: qmi_wwan: fix divide by 0 on bad descriptors
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@google.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/usb/qmi_wwan.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index 8c3733608271..a4f229edcceb 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -681,7 +681,7 @@ static int qmi_wwan_bind(struct usbnet *dev, struct usb_interface *intf) } /* 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); } |