linux/drivers/usb
Alan Stern 0a8fd13462 USB: fix problems with duplicate endpoint addresses
When checking a new device's descriptors, the USB core does not check
for duplicate endpoint addresses.  This can cause a problem when the
sysfs files for those endpoints are created; trying to create multiple
files with the same name will provoke a WARNING:

WARNING: CPU: 2 PID: 865 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x8a/0xa0
sysfs: cannot create duplicate filename
'/devices/platform/dummy_hcd.0/usb2/2-1/2-1:64.0/ep_05'
Kernel panic - not syncing: panic_on_warn set ...

CPU: 2 PID: 865 Comm: kworker/2:1 Not tainted 4.9.0-rc7+ #34
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: usb_hub_wq hub_event
 ffff88006bee64c8 ffffffff81f96b8a ffffffff00000001 1ffff1000d7dcc2c
 ffffed000d7dcc24 0000000000000001 0000000041b58ab3 ffffffff8598b510
 ffffffff81f968f8 ffffffff850fee20 ffffffff85cff020 dffffc0000000000
Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff81f96b8a>] dump_stack+0x292/0x398 lib/dump_stack.c:51
 [<ffffffff8168c88e>] panic+0x1cb/0x3a9 kernel/panic.c:179
 [<ffffffff812b80b4>] __warn+0x1c4/0x1e0 kernel/panic.c:542
 [<ffffffff812b8195>] warn_slowpath_fmt+0xc5/0x110 kernel/panic.c:565
 [<ffffffff819e70ca>] sysfs_warn_dup+0x8a/0xa0 fs/sysfs/dir.c:30
 [<ffffffff819e7308>] sysfs_create_dir_ns+0x178/0x1d0 fs/sysfs/dir.c:59
 [<     inline     >] create_dir lib/kobject.c:71
 [<ffffffff81fa1b07>] kobject_add_internal+0x227/0xa60 lib/kobject.c:229
 [<     inline     >] kobject_add_varg lib/kobject.c:366
 [<ffffffff81fa2479>] kobject_add+0x139/0x220 lib/kobject.c:411
 [<ffffffff82737a63>] device_add+0x353/0x1660 drivers/base/core.c:1088
 [<ffffffff82738d8d>] device_register+0x1d/0x20 drivers/base/core.c:1206
 [<ffffffff82cb77d3>] usb_create_ep_devs+0x163/0x260 drivers/usb/core/endpoint.c:195
 [<ffffffff82c9f27b>] create_intf_ep_devs+0x13b/0x200 drivers/usb/core/message.c:1030
 [<ffffffff82ca39d3>] usb_set_configuration+0x1083/0x18d0 drivers/usb/core/message.c:1937
 [<ffffffff82cc9e2e>] generic_probe+0x6e/0xe0 drivers/usb/core/generic.c:172
 [<ffffffff82caa7fa>] usb_probe_device+0xaa/0xe0 drivers/usb/core/driver.c:263

This patch prevents the problem by checking for duplicate endpoint
addresses during enumeration and skipping any duplicates.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-05 19:38:40 +01:00
..
atm Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
c67x00 c67x00-hcd: use USB_DT_HUB 2015-04-03 19:03:16 +02:00
chipidea ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
class USB: cdc-acm: add device id for GW Instek AFG-125 2016-12-05 16:32:51 +01:00
common usb: patches for v4.9 merge window 2016-09-14 20:37:50 +02:00
core USB: fix problems with duplicate endpoint addresses 2017-01-05 19:38:40 +01:00
dwc2 usb: dwc2: fix flags for DMA descriptor allocation in dwc2_hsotg_ep_enable 2017-01-02 10:55:28 +02:00
dwc3 usb: dwc3: gadget: Fix full speed mode 2017-01-03 14:33:48 +02:00
early treewide: remove redundant #include <linux/kconfig.h> 2016-10-11 15:06:33 -07:00
gadget usb: gadget: Fix copy/pasted error message 2017-01-03 14:33:59 +02:00
host usb: ohci-at91: use descriptor-based gpio APIs correctly 2017-01-05 19:32:29 +01:00
image usb: microtek: Use "foo *bar" instead of "foo * bar". 2016-06-07 22:18:39 -07:00
isp1760 usb: Convert pr_warning to pr_warn 2016-11-03 10:38:36 +02:00
misc Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mon Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mtu3 usb: mtu3: fix U3 port link issue 2016-12-07 09:37:24 +01:00
musb usb: musb: blackfin: add bfin_fifo_offset in bfin_ops 2017-01-05 19:18:05 +01:00
phy usb: twl6030-usb: make driver DT only 2016-11-18 13:54:44 +02:00
renesas_usbhs usb: renesas_usbhs: cleanup with list_first_entry_or_null() 2016-11-03 10:38:37 +02:00
serial USB: serial: ti_usb_3410_5052: fix NULL-deref at open 2017-01-04 10:43:57 +01:00
storage usb: storage: unusual_uas: Add JMicron JMS56x to unusual device 2017-01-05 19:24:55 +01:00
usbip usbip: fix warning in vhci_hcd_probe/lockdep_init_map 2016-12-06 08:37:41 +01:00
wusbcore usb: fix improper return value when kzalloc fails 2016-11-29 17:36:43 +01:00
Kconfig usb: Add MediaTek USB3 DRD driver 2016-10-27 17:02:41 +02:00
Makefile usb: Add MediaTek USB3 DRD driver 2016-10-27 17:02:41 +02:00
README
usb-skeleton.c usb: usb-skeleton: don't print on ENOMEM 2016-08-30 19:17:39 +02:00

To understand all the Linux-USB framework, you'll use these resources:

    * This source code.  This is necessarily an evolving work, and
      includes kerneldoc that should help you get a current overview.
      ("make pdfdocs", and then look at "usb.pdf" for host side and
      "gadget.pdf" for peripheral side.)  Also, Documentation/usb has
      more information.

    * The USB 2.0 specification (from www.usb.org), with supplements
      such as those for USB OTG and the various device classes.
      The USB specification has a good overview chapter, and USB
      peripherals conform to the widely known "Chapter 9".

    * Chip specifications for USB controllers.  Examples include
      host controllers (on PCs, servers, and more); peripheral
      controllers (in devices with Linux firmware, like printers or
      cell phones); and hard-wired peripherals like Ethernet adapters.

    * Specifications for other protocols implemented by USB peripheral
      functions.  Some are vendor-specific; others are vendor-neutral
      but just standardized outside of the www.usb.org team.

Here is a list of what each subdirectory here is, and what is contained in
them.

core/		- This is for the core USB host code, including the
		  usbfs files and the hub class driver ("hub_wq").

host/		- This is for USB host controller drivers.  This
		  includes UHCI, OHCI, EHCI, and others that might
		  be used with more specialized "embedded" systems.

gadget/		- This is for USB peripheral controller drivers and
		  the various gadget drivers which talk to them.


Individual USB driver directories.  A new driver should be added to the
first subdirectory in the list below that it fits into.

image/		- This is for still image drivers, like scanners or
		  digital cameras.
../input/	- This is for any driver that uses the input subsystem,
		  like keyboard, mice, touchscreens, tablets, etc.
../media/	- This is for multimedia drivers, like video cameras,
		  radios, and any other drivers that talk to the v4l
		  subsystem.
../net/		- This is for network drivers.
serial/		- This is for USB to serial drivers.
storage/	- This is for USB mass-storage drivers.
class/		- This is for all USB device drivers that do not fit
		  into any of the above categories, and work for a range
		  of USB Class specified devices. 
misc/		- This is for all USB device drivers that do not fit
		  into any of the above categories.