Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937710AbdCJOBE (ORCPT ); Fri, 10 Mar 2017 09:01:04 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42554 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934004AbdCJLvk (ORCPT ); Fri, 10 Mar 2017 06:51:40 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Andrey Konovalov" , "Greg Kroah-Hartman" , "Alan Stern" Date: Fri, 10 Mar 2017 11:46:22 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 186/370] USB: fix problems with duplicate endpoint addresses In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3520 Lines: 75 3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit 0a8fd1346254974c3a852338508e4a4cddbb35f1 upstream. 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 [] dump_stack+0x292/0x398 lib/dump_stack.c:51 [] panic+0x1cb/0x3a9 kernel/panic.c:179 [] __warn+0x1c4/0x1e0 kernel/panic.c:542 [] warn_slowpath_fmt+0xc5/0x110 kernel/panic.c:565 [] sysfs_warn_dup+0x8a/0xa0 fs/sysfs/dir.c:30 [] sysfs_create_dir_ns+0x178/0x1d0 fs/sysfs/dir.c:59 [< inline >] create_dir lib/kobject.c:71 [] kobject_add_internal+0x227/0xa60 lib/kobject.c:229 [< inline >] kobject_add_varg lib/kobject.c:366 [] kobject_add+0x139/0x220 lib/kobject.c:411 [] device_add+0x353/0x1660 drivers/base/core.c:1088 [] device_register+0x1d/0x20 drivers/base/core.c:1206 [] usb_create_ep_devs+0x163/0x260 drivers/usb/core/endpoint.c:195 [] create_intf_ep_devs+0x13b/0x200 drivers/usb/core/message.c:1030 [] usb_set_configuration+0x1083/0x18d0 drivers/usb/core/message.c:1937 [] generic_probe+0x6e/0xe0 drivers/usb/core/generic.c:172 [] 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 Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/core/config.c | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -205,6 +205,16 @@ static int usb_parse_endpoint(struct dev if (ifp->desc.bNumEndpoints >= num_ep) goto skip_to_next_endpoint_or_interface_descriptor; + /* Check for duplicate endpoint addresses */ + for (i = 0; i < ifp->desc.bNumEndpoints; ++i) { + if (ifp->endpoint[i].desc.bEndpointAddress == + d->bEndpointAddress) { + dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n", + cfgno, inum, asnum, d->bEndpointAddress); + goto skip_to_next_endpoint_or_interface_descriptor; + } + } + endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints]; ++ifp->desc.bNumEndpoints;