From 7fd078337201cf7468f53c3d9ef81ff78cb6df3b Mon Sep 17 00:00:00 2001 From: Bjørn Mork Date: Mon, 6 Nov 2017 15:32:18 +0100 Subject: net: qmi_wwan: fix divide by 0 on bad descriptors MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Bjørn Mork Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/usb/qmi_wwan.c') 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); } -- cgit From 0de0add10e587effa880c741c9413c874f16be91 Mon Sep 17 00:00:00 2001 From: Kristian Evensen Date: Tue, 7 Nov 2017 13:47:56 +0100 Subject: qmi_wwan: Add missing skb_reset_mac_header-call MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When we receive a packet on a QMI device in raw IP mode, we should call skb_reset_mac_header() to ensure that skb->mac_header contains a valid offset in the packet. While it shouldn't really matter, the packets have no MAC header and the interface is configured as-such, it seems certain parts of the network stack expects a "good" value in skb->mac_header. Without the skb_reset_mac_header() call added in this patch, for example shaping traffic (using tc) triggers the following oops on the first received packet: [ 303.642957] skbuff: skb_under_panic: text:8f137918 len:177 put:67 head:8e4b0f00 data:8e4b0eff tail:0x8e4b0fb0 end:0x8e4b1520 dev:wwan0 [ 303.655045] Kernel bug detected[#1]: [ 303.658622] CPU: 1 PID: 1002 Comm: logd Not tainted 4.9.58 #0 [ 303.664339] task: 8fdf05e0 task.stack: 8f15c000 [ 303.668844] $ 0 : 00000000 00000001 0000007a 00000000 [ 303.674062] $ 4 : 8149a2fc 8149a2fc 8149ce20 00000000 [ 303.679284] $ 8 : 00000030 3878303a 31623465 20303235 [ 303.684510] $12 : ded731e3 2626a277 00000000 03bd0000 [ 303.689747] $16 : 8ef62b40 00000043 8f137918 804db5fc [ 303.694978] $20 : 00000001 00000004 8fc13800 00000003 [ 303.700215] $24 : 00000001 8024ab10 [ 303.705442] $28 : 8f15c000 8fc19cf0 00000043 802cc920 [ 303.710664] Hi : 00000000 [ 303.713533] Lo : 74e58000 [ 303.716436] epc : 802cc920 skb_panic+0x58/0x5c [ 303.721046] ra : 802cc920 skb_panic+0x58/0x5c [ 303.725639] Status: 11007c03 KERNEL EXL IE [ 303.729823] Cause : 50800024 (ExcCode 09) [ 303.733817] PrId : 0001992f (MIPS 1004Kc) [ 303.737892] Modules linked in: rt2800pci rt2800mmio rt2800lib qcserial ppp_async option usb_wwan rt2x00pci rt2x00mmio rt2x00lib rndis_host qmi_wwan ppp_generic nf_nat_pptp nf_conntrack_pptp nf_conntrack_ipv6 mt76x2i Process logd (pid: 1002, threadinfo=8f15c000, task=8fdf05e0, tls=77b3eee4) [ 303.962509] Stack : 00000000 80408990 8f137918 000000b1 00000043 8e4b0f00 8e4b0eff 8e4b0fb0 [ 303.970871] 8e4b1520 8fec1800 00000043 802cd2a4 6e000045 00000043 00000000 8ef62000 [ 303.979219] 8eef5d00 8ef62b40 8fea7300 8f137918 00000000 00000000 0002bb01 793e5664 [ 303.987568] 8ef08884 00000001 8fea7300 00000002 8fc19e80 8eef5d00 00000006 00000003 [ 303.995934] 00000000 8030ba90 00000003 77ab3fd0 8149dc80 8004d1bc 8f15c000 8f383700 [ 304.004324] ... [ 304.006767] Call Trace: [ 304.009241] [<802cc920>] skb_panic+0x58/0x5c [ 304.013504] [<802cd2a4>] skb_push+0x78/0x90 [ 304.017783] [<8f137918>] 0x8f137918 [ 304.021269] Code: 00602825 0c02a3b4 24842888 <000c000d> 8c870060 8c8200a0 0007382b 00070336 8c88005c [ 304.031034] [ 304.032805] ---[ end trace b778c482b3f0bda9 ]--- [ 304.041384] Kernel panic - not syncing: Fatal exception in interrupt [ 304.051975] Rebooting in 3 seconds.. While the oops is for a 4.9-kernel, I was able to trigger the same oops with net-next as of yesterday. Fixes: 32f7adf633b9 ("net: qmi_wwan: support "raw IP" mode") Signed-off-by: Kristian Evensen Acked-by: Bjørn Mork Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/net/usb/qmi_wwan.c') diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index a4f229edcceb..8d4a6f7cba61 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -499,6 +499,7 @@ static int qmi_wwan_rx_fixup(struct usbnet *dev, struct sk_buff *skb) return 1; } if (rawip) { + skb_reset_mac_header(skb); skb->dev = dev->net; /* normally set by eth_type_trans */ skb->protocol = proto; return 1; -- cgit