USB: g_file_storage: ignore bulk-out data after invalid CBW

This patch (as1061) makes g_file_storage more compliant with the
Bulk-Only Transport specification.  After an invalid CBW is received,
the gadget must ignore any further bulk-OUT data until it is reset.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern 2008-04-14 11:45:29 -04:00 committed by Greg Kroah-Hartman
parent 9aebfd6bda
commit b950bdbc67

View File

@ -644,7 +644,7 @@ struct fsg_dev {
unsigned long atomic_bitflags;
#define REGISTERED 0
#define CLEAR_BULK_HALTS 1
#define IGNORE_BULK_OUT 1
#define SUSPENDED 2
struct usb_ep *bulk_in;
@ -2936,8 +2936,8 @@ static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
struct usb_request *req = bh->outreq;
struct bulk_cb_wrap *cbw = req->buf;
/* Was this a real packet? */
if (req->status)
/* Was this a real packet? Should it be ignored? */
if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
return -EINVAL;
/* Is the CBW valid? */
@ -2948,13 +2948,17 @@ static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
req->actual,
le32_to_cpu(cbw->Signature));
/* The Bulk-only spec says we MUST stall the bulk pipes!
* If we want to avoid stalls, set a flag so that we will
* clear the endpoint halts at the next reset. */
if (!mod_data.can_stall)
set_bit(CLEAR_BULK_HALTS, &fsg->atomic_bitflags);
fsg_set_halt(fsg, fsg->bulk_out);
/* The Bulk-only spec says we MUST stall the IN endpoint
* (6.6.1), so it's unavoidable. It also says we must
* retain this state until the next reset, but there's
* no way to tell the controller driver it should ignore
* Clear-Feature(HALT) requests.
*
* We aren't required to halt the OUT endpoint; instead
* we can simply accept and discard any data received
* until the next reset. */
halt_bulk_in_endpoint(fsg);
set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
return -EINVAL;
}
@ -3140,6 +3144,7 @@ reset:
goto reset;
fsg->bulk_out_enabled = 1;
fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
if (transport_is_cbi()) {
d = ep_desc(fsg->gadget, &fs_intr_in_desc, &hs_intr_in_desc);
@ -3321,11 +3326,8 @@ static void handle_exception(struct fsg_dev *fsg)
/* In case we were forced against our will to halt a
* bulk endpoint, clear the halt now. (The SuperH UDC
* requires this.) */
if (test_and_clear_bit(CLEAR_BULK_HALTS,
&fsg->atomic_bitflags)) {
if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
usb_ep_clear_halt(fsg->bulk_in);
usb_ep_clear_halt(fsg->bulk_out);
}
if (transport_is_bbb()) {
if (fsg->ep0_req_tag == exception_req_tag)