[PATCH] USB: gadget: epautoconf: fix ep maxpacket check

From: Robert Baldyga
Date: Fri Sep 27 2013 - 06:30:32 EST


This patch fixes validation of maxpacket value given in endpoint descriptor.
Added check of maxpacket for bulk endpoints.
Correct maxpacket value is:

FULL-SPEED HIGH-SPEED
BULK 64 512
INTERRUPT 64 1024
ISOCHRONOUS 1023 1024

Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
---
drivers/usb/gadget/epautoconf.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/gadget/epautoconf.c b/drivers/usb/gadget/epautoconf.c
index a777f7b..35bde34 100644
--- a/drivers/usb/gadget/epautoconf.c
+++ b/drivers/usb/gadget/epautoconf.c
@@ -136,16 +136,26 @@ ep_matches (
* the usb spec fixes high speed bulk maxpacket at 512 bytes.
*/
max = 0x7ff & usb_endpoint_maxp(desc);
+
+ if (ep->maxpacket < max)
+ return 0;
+
switch (type) {
+ case USB_ENDPOINT_XFER_BULK:
+ /* BULK: limit 512 high/super speed */
+ if (max > 512)
+ return 0;
+ /* FALLTHROUGH */
+
case USB_ENDPOINT_XFER_INT:
- /* INT: limit 64 bytes full speed, 1024 high/super speed */
+ /* BULK/INT: limit 64 bytes full speed */
if (!gadget_is_dualspeed(gadget) && max > 64)
return 0;
/* FALLTHROUGH */

case USB_ENDPOINT_XFER_ISOC:
- /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
- if (ep->maxpacket < max)
+ /* INT/ISO: limit 1023 bytes full speed, 1024 high/super speed */
+ if (max > 1024)
return 0;
if (!gadget_is_dualspeed(gadget) && max > 1023)
return 0;
--
1.7.9.5

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