linux-kernel - [PATCH v2][RESEND] usb: gadget: core: Fix ->udc_set

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <cbf14127-e788-0c51-4daa-2b25eec60b47@ti.com>
Date:   Tue, 31 Oct 2017 15:56:29 +0200
From:   Roger Quadros <rogerq@...com>
To:     <balbi@...nel.org>
CC:     <Dylan.Howey@...nantco.com>, <linux-usb@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>,
        "# v4 . 13+" <stable@...r.kernel.org>, <rogerq@...com>
Subject: [PATCH v2][RESEND] usb: gadget: core: Fix ->udc_set_speed() speed
 handling

Currently UDC core calls ->udc_set_speed() with the speed parameter
containing the maximum speed supported by the gadget function
driver. This might very well be more than that supported by the
UDC controller driver.

Select the lesser of the 2 speeds so both UDC and gadget function
driver are operating within limits.

This fixes PHY Erratic errors and 2 second enumeration delay on
TI's AM437x platforms.

Fixes: 6099eca796ae ("usb: gadget: core: introduce ->udc_set_speed() method")
Cc: <stable@...r.kernel.org> # v4.13+
Reported-by: Dylan Howey <Dylan.Howey@...nantco.com>
Signed-off-by: Roger Quadros <rogerq@...com>
---
v2:
- Move speed limiting code to UDC core.

 drivers/usb/gadget/udc/core.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index d41d07a..def1b05 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -1080,8 +1080,12 @@ static inline void usb_gadget_udc_stop(struct usb_udc *udc)
 static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
 					    enum usb_device_speed speed)
 {
-	if (udc->gadget->ops->udc_set_speed)
-		udc->gadget->ops->udc_set_speed(udc->gadget, speed);
+	if (udc->gadget->ops->udc_set_speed) {
+		enum usb_device_speed s;
+
+		s = min(speed, udc->gadget->max_speed);
+		udc->gadget->ops->udc_set_speed(udc->gadget, s);
+	}
 }
 
 /**
-- 
cheers,
-roger

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki