bcdbeb8447
The stop_activity() routine in dummy-hcd is supposed to unlink all active requests for every endpoint, among other things. But it doesn't handle ep0. As a result, fuzz testing can generate a WARNING like the following: WARNING: CPU: 0 PID: 4410 at drivers/usb/gadget/udc/dummy_hcd.c:672 dummy_free_request+0x153/0x170 Modules linked in: CPU: 0 PID: 4410 Comm: syz-executor Not tainted 4.9.0-rc7+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff88006a64ed10 ffffffff81f96b8a ffffffff41b58ab3 1ffff1000d4c9d35 ffffed000d4c9d2d ffff880065f8ac00 0000000041b58ab3 ffffffff8598b510 ffffffff81f968f8 0000000041b58ab3 ffffffff859410e0 ffffffff813f0590 Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81f96b8a>] dump_stack+0x292/0x398 lib/dump_stack.c:51 [<ffffffff812b808f>] __warn+0x19f/0x1e0 kernel/panic.c:550 [<ffffffff812b831c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585 [<ffffffff830fcb13>] dummy_free_request+0x153/0x170 drivers/usb/gadget/udc/dummy_hcd.c:672 [<ffffffff830ed1b0>] usb_ep_free_request+0xc0/0x420 drivers/usb/gadget/udc/core.c:195 [<ffffffff83225031>] gadgetfs_unbind+0x131/0x190 drivers/usb/gadget/legacy/inode.c:1612 [<ffffffff830ebd8f>] usb_gadget_remove_driver+0x10f/0x2b0 drivers/usb/gadget/udc/core.c:1228 [<ffffffff830ec084>] usb_gadget_unregister_driver+0x154/0x240 drivers/usb/gadget/udc/core.c:1357 This patch fixes the problem by iterating over all the endpoints in the driver's ep array instead of iterating over the gadget's ep_list, which explicitly leaves out ep0. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Andrey Konovalov <andreyknvl@google.com> CC: <stable@vger.kernel.org> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.