Patch "usb: renesas_usbhs: protect the CFIFOSEL setting in usbhsg_ep_enable()" has been added to the 4.7-stable tree

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

usb: renesas_usbhs: protect the CFIFOSEL setting in usbhsg_ep_enable()

to the 4.7-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-renesas_usbhs-protect-the-cfifosel-setting-in-usbhsg_ep_enable.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Yoshihiro Shimoda <[email protected]>
Date: Wed, 8 Jun 2016 16:32:50 +0900
Subject: usb: renesas_usbhs: protect the CFIFOSEL setting in usbhsg_ep_enable()

From: Yoshihiro Shimoda <[email protected]>

commit 15e4292a2d21e9997fdb2b8c014cc461b3f268f0 upstream.

This patch fixes an issue that the CFIFOSEL register value is possible to be changed by usbhsg_ep_enable() wrongly. And then, a data transfer using CFIFO may not work correctly.

For example:

 # modprobe g_multi file=usb-storage.bin
 # ifconfig usb0 192.168.1.1 up
 (During the USB host is sending file to the mass storage)
 # ifconfig usb0 down

In this case, since the u_ether.c may call usb_ep_enable() in eth_stop(), if the renesas_usbhs driver is also using CFIFO for mass storage, the mass storage may not work correctly.

So, this patch adds usbhs_lock() and usbhs_unlock() calling in usbhsg_ep_enable() to protect CFIFOSEL register. This is because:
- CFIFOSEL.CURPIPE = 0 is also needed for the pipe configuration
- The CFIFOSEL (fifo->sel) is already protected by usbhs_lock()

---
 drivers/usb/renesas_usbhs/mod_gadget.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

@@ -585,6 +585,9 @@ static int usbhsg_ep_enable(struct usb_e
 	struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
 	struct usbhs_pipe *pipe;
 	int ret = -EIO;
+	unsigned long flags;
+
+	usbhs_lock(priv, flags);
 
 	/*
 	 * if it already have pipe,

@@ -593,7 +596,8 @@ static int usbhsg_ep_enable(struct usb_e
 	if (uep->pipe) {
 		usbhs_pipe_clear(uep->pipe);
 		usbhs_pipe_sequence_data0(uep->pipe);
-		return 0;
+		ret = 0;
+		goto usbhsg_ep_enable_end;
 	}
 
 	pipe = usbhs_pipe_malloc(priv,

@@ -621,6 +625,9 @@ static int usbhsg_ep_enable(struct usb_e
 		ret = 0;
 	}
 
+usbhsg_ep_enable_end:
+	usbhs_unlock(priv, flags);
+
 	return ret;
 }
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.7/usb-renesas_usbhs-protect-the-cfifosel-setting-in-usbhsg_ep_enable.patch queue-4.7/usb-renesas_usbhs-fix-null-pointer-dereference-in-xfer_work.patch