On Wed, Dec 18, 2019 at 8:27 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote: > > This patchset (currently a single patch) adds a new userspace interface > for the USB Gadget subsystem called USB Raw Gadget (I don't mind changing > the name to something else if there are better ideas). This is what > currently being used to enable coverage-buided USB fuzzing with syzkaller: > > https://github.com/google/syzkaller/blob/master/docs/linux/external_fuzzing_usb.md > > Initially I was using GadgetFS (together with the Dummy HCD/UDC module) > to perform emulation of USB devices for fuzzing, but later switched to a > custom written interface. The incentive to implement a different interface > was to provide a somewhat raw and direct access to the USB Gadget layer > for the userspace, where every USB request is passed to the userspace to > get a response. See documentation for the list of differences between > Raw Gadget and GadgetFS. > > This patchset has been pushed to the public Linux kernel Gerrit instance: > > https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/2144 Hi Greg, Just an after holidays reminder that I've sent v4 of this patchset and looking forward to a review. Thanks! > > Changes v3 -> v4: > - Print debug message when maxpacket check fails. > - Use module_misc_device() instead of module_init/exit(). > - Reuse DRIVER_NAME macro in raw_device struct definition. > - Don't print WARNING in raw_release(). > - Add comment that explains locking into raw_event_queue_fetch(). > - Print a WARNING when event queue size is exceeded. > - Rename raw.c to raw_gadget.c. > - Mention module name in Kconfig. > - Reworked logging to use dev_err/dbg() instead of pr_err/debug(). > > Changes v2 -> v3: > - Updated device path in documentation. > - Changed usb_raw_init struct layout to make it the same for 32 bit compat > mode. > - Added compat_ioctl to raw_fops. > - Changed raw_ioctl_init() to return EINVAL for invalid USB speeds, except > for USB_SPEED_UNKNOWN, which defaults to USB_SPEED_HIGH. > - Reject endpoints with maxpacket = 0 in raw_ioctl_ep_enable(). > > Changes v1 -> v2: > - Moved raw.c to legacy/. > - Changed uapi header to use __u* types. > - Switched from debugfs entry to a misc device. > - Changed raw_dev from refcount to kref. > - Moved UDC_NAME_LENGTH_MAX to uapi headers. > - Used usb_endpoint_type() and usb_endpoint_dir_in/out() functions instead > of open coding them. > - Added "WITH Linux-syscall-note" to SPDX id in the uapi header. > - Removed pr_err() if case dev_new() fails. > - Reduced the number of debugging messages. > > Andrey Konovalov (1): > usb: gadget: add raw-gadget interface > > Documentation/usb/index.rst | 1 + > Documentation/usb/raw-gadget.rst | 59 ++ > drivers/usb/gadget/legacy/Kconfig | 11 + > drivers/usb/gadget/legacy/Makefile | 1 + > drivers/usb/gadget/legacy/raw_gadget.c | 1071 ++++++++++++++++++++++++ > include/uapi/linux/usb/raw_gadget.h | 167 ++++ > 6 files changed, 1310 insertions(+) > create mode 100644 Documentation/usb/raw-gadget.rst > create mode 100644 drivers/usb/gadget/legacy/raw_gadget.c > create mode 100644 include/uapi/linux/usb/raw_gadget.h > > -- > 2.24.1.735.g03f4e72817-goog >
