Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965021AbdCJJzE (ORCPT ); Fri, 10 Mar 2017 04:55:04 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:42690 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935657AbdCJJeW (ORCPT ); Fri, 10 Mar 2017 04:34:22 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Lechner , Krzysztof Opasiak , Felipe Balbi Subject: [PATCH 4.10 120/167] usb: gadget: f_hid: fix: Move IN request allocation to set_alt() Date: Fri, 10 Mar 2017 10:09:23 +0100 Message-Id: <20170310084003.306024340@linuxfoundation.org> X-Mailer: git-send-email 2.12.0 In-Reply-To: <20170310083956.767605269@linuxfoundation.org> References: <20170310083956.767605269@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6284 Lines: 228 4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Krzysztof Opasiak commit 749494b6bdbbaf0899aa1c62a1ad74cd747bce47 upstream. Since commit: ba1582f22231 ("usb: gadget: f_hid: use alloc_ep_req()") we cannot allocate any requests in bind() as we check if we should align request buffer based on endpoint descriptor which is assigned in set_alt(). Allocating request in bind() function causes a NULL pointer dereference. This commit moves allocation of IN request from bind() to set_alt() to prevent this issue. Fixes: ba1582f22231 ("usb: gadget: f_hid: use alloc_ep_req()") Tested-by: David Lechner Signed-off-by: Krzysztof Opasiak Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_hid.c | 89 +++++++++++++++++++++++++++--------- 1 file changed, 67 insertions(+), 22 deletions(-) --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -338,6 +338,7 @@ static ssize_t f_hidg_write(struct file size_t count, loff_t *offp) { struct f_hidg *hidg = file->private_data; + struct usb_request *req; unsigned long flags; ssize_t status = -ENOMEM; @@ -347,7 +348,7 @@ static ssize_t f_hidg_write(struct file spin_lock_irqsave(&hidg->write_spinlock, flags); #define WRITE_COND (!hidg->write_pending) - +try_again: /* write queue */ while (!WRITE_COND) { spin_unlock_irqrestore(&hidg->write_spinlock, flags); @@ -362,6 +363,7 @@ static ssize_t f_hidg_write(struct file } hidg->write_pending = 1; + req = hidg->req; count = min_t(unsigned, count, hidg->report_length); spin_unlock_irqrestore(&hidg->write_spinlock, flags); @@ -374,24 +376,38 @@ static ssize_t f_hidg_write(struct file goto release_write_pending; } - hidg->req->status = 0; - hidg->req->zero = 0; - hidg->req->length = count; - hidg->req->complete = f_hidg_req_complete; - hidg->req->context = hidg; + spin_lock_irqsave(&hidg->write_spinlock, flags); + + /* we our function has been disabled by host */ + if (!hidg->req) { + free_ep_req(hidg->in_ep, hidg->req); + /* + * TODO + * Should we fail with error here? + */ + goto try_again; + } + + req->status = 0; + req->zero = 0; + req->length = count; + req->complete = f_hidg_req_complete; + req->context = hidg; status = usb_ep_queue(hidg->in_ep, hidg->req, GFP_ATOMIC); if (status < 0) { ERROR(hidg->func.config->cdev, "usb_ep_queue error on int endpoint %zd\n", status); - goto release_write_pending; + goto release_write_pending_unlocked; } else { status = count; } + spin_unlock_irqrestore(&hidg->write_spinlock, flags); return status; release_write_pending: spin_lock_irqsave(&hidg->write_spinlock, flags); +release_write_pending_unlocked: hidg->write_pending = 0; spin_unlock_irqrestore(&hidg->write_spinlock, flags); @@ -595,12 +611,23 @@ static void hidg_disable(struct usb_func kfree(list); } spin_unlock_irqrestore(&hidg->read_spinlock, flags); + + spin_lock_irqsave(&hidg->write_spinlock, flags); + if (!hidg->write_pending) { + free_ep_req(hidg->in_ep, hidg->req); + hidg->write_pending = 1; + } + + hidg->req = NULL; + spin_unlock_irqrestore(&hidg->write_spinlock, flags); } static int hidg_set_alt(struct usb_function *f, unsigned intf, unsigned alt) { struct usb_composite_dev *cdev = f->config->cdev; struct f_hidg *hidg = func_to_hidg(f); + struct usb_request *req_in = NULL; + unsigned long flags; int i, status = 0; VDBG(cdev, "hidg_set_alt intf:%d alt:%d\n", intf, alt); @@ -621,6 +648,12 @@ static int hidg_set_alt(struct usb_funct goto fail; } hidg->in_ep->driver_data = hidg; + + req_in = hidg_alloc_ep_req(hidg->in_ep, hidg->report_length); + if (!req_in) { + status = -ENOMEM; + goto disable_ep_in; + } } @@ -632,12 +665,12 @@ static int hidg_set_alt(struct usb_funct hidg->out_ep); if (status) { ERROR(cdev, "config_ep_by_speed FAILED!\n"); - goto fail; + goto free_req_in; } status = usb_ep_enable(hidg->out_ep); if (status < 0) { ERROR(cdev, "Enable OUT endpoint FAILED!\n"); - goto fail; + goto free_req_in; } hidg->out_ep->driver_data = hidg; @@ -653,17 +686,37 @@ static int hidg_set_alt(struct usb_funct req->context = hidg; status = usb_ep_queue(hidg->out_ep, req, GFP_ATOMIC); - if (status) + if (status) { ERROR(cdev, "%s queue req --> %d\n", hidg->out_ep->name, status); + free_ep_req(hidg->out_ep, req); + } } else { - usb_ep_disable(hidg->out_ep); status = -ENOMEM; - goto fail; + goto disable_out_ep; } } } + if (hidg->in_ep != NULL) { + spin_lock_irqsave(&hidg->write_spinlock, flags); + hidg->req = req_in; + hidg->write_pending = 0; + spin_unlock_irqrestore(&hidg->write_spinlock, flags); + + wake_up(&hidg->write_queue); + } + return 0; +disable_out_ep: + usb_ep_disable(hidg->out_ep); +free_req_in: + if (req_in) + free_ep_req(hidg->in_ep, req_in); + +disable_ep_in: + if (hidg->in_ep) + usb_ep_disable(hidg->in_ep); + fail: return status; } @@ -712,12 +765,6 @@ static int hidg_bind(struct usb_configur goto fail; hidg->out_ep = ep; - /* preallocate request and buffer */ - status = -ENOMEM; - hidg->req = alloc_ep_req(hidg->in_ep, hidg->report_length); - if (!hidg->req) - goto fail; - /* set descriptor dynamic values */ hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass; hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol; @@ -755,6 +802,8 @@ static int hidg_bind(struct usb_configur goto fail; spin_lock_init(&hidg->write_spinlock); + hidg->write_pending = 1; + hidg->req = NULL; spin_lock_init(&hidg->read_spinlock); init_waitqueue_head(&hidg->write_queue); init_waitqueue_head(&hidg->read_queue); @@ -1019,10 +1068,6 @@ static void hidg_unbind(struct usb_confi device_destroy(hidg_class, MKDEV(major, hidg->minor)); cdev_del(&hidg->cdev); - /* disable/free request and end point */ - usb_ep_disable(hidg->in_ep); - free_ep_req(hidg->in_ep, hidg->req); - usb_free_all_descriptors(f); }