[PATCH 2/9] usb: gadget: align buffer size when allocating for OUT endpoint

From: Felipe F. Tonello
Date: Tue Jul 26 2016 - 15:15:57 EST


Using usb_ep_align() makes sure that the buffer size for OUT endpoints is
always aligned with wMaxPacketSize (512 usually). This makes sure
that no buffer has the wrong size, which can cause nasty bugs.

Signed-off-by: Felipe F. Tonello <eu@xxxxxxxxxxxxxxxxx>
---
drivers/usb/gadget/u_f.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/usb/gadget/u_f.c b/drivers/usb/gadget/u_f.c
index 4bc7eea8bfc8..d1933b0b76c3 100644
--- a/drivers/usb/gadget/u_f.c
+++ b/drivers/usb/gadget/u_f.c
@@ -12,6 +12,7 @@
*/

#include "u_f.h"
+#include <linux/usb/ch9.h>

struct usb_request *alloc_ep_req(struct usb_ep *ep, int len, int default_len)
{
@@ -20,6 +21,8 @@ struct usb_request *alloc_ep_req(struct usb_ep *ep, int len, int default_len)
req = usb_ep_alloc_request(ep, GFP_ATOMIC);
if (req) {
req->length = len ?: default_len;
+ if (usb_endpoint_dir_out(ep->desc))
+ req->length = usb_ep_align(ep, req->length);
req->buf = kmalloc(req->length, GFP_ATOMIC);
if (!req->buf) {
usb_ep_free_request(ep, req);
--
2.9.0