USB: less-restrictive command checking in g-file-storage

This patch (as983) makes a test for minimum-length command sizes in
g_file_storage less restrictive.  It doesn't matter because commands
with bad lengths will be detected later on anyway, and doing it like
this makes the driver interoperable with certain buggy hosts such as
the JVC HiFi (reported by Samuel Hangouet).

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index 9998cd7af41843353ffee292f895976d8dc3929b..0551140010eea28188ab7ecc66df692964138052 100644 (file)
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -2964,7 +2964,7 @@ static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 
        /* Is the CBW meaningful? */
        if (cbw->Lun >= MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
-                       cbw->Length < 6 || cbw->Length > MAX_COMMAND_SIZE) {
+                       cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
                DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
                                "cmdlen %u\n",
                                cbw->Lun, cbw->Flags, cbw->Length);