Patch "usb: dwc3: ep0: Fix mem corruption on OUT transfers of more than 512 bytes" has been added to the 4.1-stable tree

Patch "usb: dwc3: ep0: Fix mem corruption on OUT transfers of more than 512 bytes" has been added to the 4.1-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    usb: dwc3: ep0: Fix mem corruption on OUT transfers of more than 512 bytes

to the 4.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-dwc3-ep0-fix-mem-corruption-on-out-transfers-of-more-than-512-bytes.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From b2fb5b1a0f50d3ebc12342c8d8dead245e9c9d4e Mon Sep 17 00:00:00 2001
From: Kishon Vijay Abraham I <kishon@ti.com>
Date: Mon, 27 Jul 2015 12:25:27 +0530
Subject: usb: dwc3: ep0: Fix mem corruption on OUT transfers of more than 512 bytes

From: Kishon Vijay Abraham I <kishon@ti.com>

commit b2fb5b1a0f50d3ebc12342c8d8dead245e9c9d4e upstream.

DWC3 uses bounce buffer to handle non max packet aligned OUT transfers and
the size of bounce buffer is 512 bytes. However if the host initiates OUT
transfers of size more than 512 bytes (and non max packet aligned), the
driver throws a WARN dump but still programs the TRB to receive more than
512 bytes. This will cause bounce buffer to overflow and corrupt the
adjacent memory locations which can be fatal.

Fix it by programming the TRB to receive a maximum of DWC3_EP0_BOUNCE_SIZE
(512) bytes.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/dwc3/ep0.c |   12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -820,6 +820,11 @@ static void dwc3_ep0_complete_data(struc
 		unsigned maxp = ep0->endpoint.maxpacket;
 
 		transfer_size += (maxp - (transfer_size % maxp));
+
+		/* Maximum of DWC3_EP0_BOUNCE_SIZE can only be received */
+		if (transfer_size > DWC3_EP0_BOUNCE_SIZE)
+			transfer_size = DWC3_EP0_BOUNCE_SIZE;
+
 		transferred = min_t(u32, ur->length,
 				transfer_size - length);
 		memcpy(ur->buf, dwc->ep0_bounce, transferred);
@@ -941,11 +946,14 @@ static void __dwc3_ep0_do_control_data(s
 			return;
 		}
 
-		WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE);
-
 		maxpacket = dep->endpoint.maxpacket;
 		transfer_size = roundup(req->request.length, maxpacket);
 
+		if (transfer_size > DWC3_EP0_BOUNCE_SIZE) {
+			dev_WARN(dwc->dev, "bounce buf can't handle req len\n");
+			transfer_size = DWC3_EP0_BOUNCE_SIZE;
+		}
+
 		dwc->ep0_bounced = true;
 
 		/*


Patches currently in stable-queue which might be from kishon@ti.com are

queue-4.1/usb-dwc3-ep0-fix-mem-corruption-on-out-transfers-of-more-than-512-bytes.patch