| Filename | Latest commit message | Latest commit date |
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21851aa886
[ Upstream commit ac854131d9844f79e2fdcef67a7707227538d78a ] The syzbot fuzzer found a race between URB submission to endpoint 0 and device reset. Namely, during the reset we call usb_ep0_reinit() because the characteristics of ep0 may have changed (if the reset follows a firmware update, for example). While usb_ep0_reinit() is running there is a brief period during which the pointers stored in udev->ep_in[0] and udev->ep_out[0] are set to NULL, and if an URB is submitted to ep0 during that period, usb_urb_ep_type_check() will report it as a driver bug. In the absence of those pointers, the routine thinks that the endpoint doesn't exist. The log message looks like this: ------------[ cut here ]------------ usb 2-1: BOGUS urb xfer, pipe 2 != type 2 WARNING: CPU: 0 PID: 9241 at drivers/usb/core/urb.c:478 usb_submit_urb+0x1188/0x1460 drivers/usb/core/urb.c:478 Now, although submitting an URB while the device is being reset is a questionable thing to do, it shouldn't count as a driver bug as severe as submitting an URB for an endpoint that doesn't exist. Indeed, endpoint 0 always exists, even while the device is in its unconfigured state. To prevent these misleading driver bug reports, this patch updates usb_disable_endpoint() to avoid clearing the ep_in[] and ep_out[] pointers when the endpoint being disabled is ep0. There's no danger of leaving a stale pointer in place, because the usb_host_endpoint structure being pointed to is stored permanently in udev->ep0; it doesn't get deallocated until the entire usb_device structure does. Reported-and-tested-by: syzbot+db339689b2101f6f6071@syzkaller.appspotmail.com Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2005011558590.903-100000@netrider.rowland.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> |
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| atm | ||
| c67x00 | ||
| chipidea | ||
| class | ||
| common | ||
| core | ||
| dwc2 | ||
| dwc3 | ||
| early | ||
| gadget | ||
| host | ||
| image | ||
| isp1760 | ||
| misc | ||
| mon | ||
| musb | ||
| phy | ||
| renesas_usbhs | ||
| serial | ||
| storage | ||
| usbip | ||
| wusbcore | ||
| Kconfig | ||
| Makefile | ||
| README | ||
| usb-skeleton.c | ||
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.