Fix LibUSB v1.0 compliancy.

1) We need to allow the USB callback to free the USB transfer itself.
2) The USB transfer buffer should only be automatically freed when
freeing the USB transfer.

Fixed by:	hselasky
Submitted by:	Gustau Perez i Querol
Approved by:	thompsa (mentor)

2 files changed, 11 insertions, 4 deletions

diff --git a/lib/libusb/libusb10.c b/lib/libusb/libusb10.c
index 5767cb2..3b8d567 100644
--- a/lib/libusb/libusb10.c
+++ b/lib/libusb/libusb10.c
@@ -800,6 +800,10 @@ libusb_free_transfer(struct libusb_transfer *uxfer)
 	if (uxfer == NULL)
 		return;			/* be NULL safe */
 
+	/* check if we should free the transfer buffer */
+	if (uxfer->flags & LIBUSB_TRANSFER_FREE_BUFFER)
+		free(uxfer->buffer);
+
 	sxfer = (struct libusb_super_transfer *)(
 	    (uint8_t *)uxfer - sizeof(*sxfer));
 
diff --git a/lib/libusb/libusb10_io.c b/lib/libusb/libusb10_io.c
index 48405c9..380e312 100644
--- a/lib/libusb/libusb10_io.c
+++ b/lib/libusb/libusb10_io.c
@@ -187,6 +187,8 @@ do_done:
 	/* Do all done callbacks */
 
 	while ((sxfer = TAILQ_FIRST(&ctx->tr_done))) {
+		uint8_t flags;
+
 		TAILQ_REMOVE(&ctx->tr_done, sxfer, entry);
 		sxfer->entry.tqe_prev = NULL;
 
@@ -197,13 +199,14 @@ do_done:
 		uxfer = (struct libusb_transfer *)(
 		    ((uint8_t *)sxfer) + sizeof(*sxfer));
 
+		/* Allow the callback to free the transfer itself. */
+		flags = uxfer->flags;
+
 		if (uxfer->callback != NULL)
 			(uxfer->callback) (uxfer);
 
-		if (uxfer->flags & LIBUSB_TRANSFER_FREE_BUFFER)
-			free(uxfer->buffer);
-
-		if (uxfer->flags & LIBUSB_TRANSFER_FREE_TRANSFER)
+		/* Check if the USB transfer should be automatically freed. */
+		if (flags & LIBUSB_TRANSFER_FREE_TRANSFER)
 			libusb_free_transfer(uxfer);
 
 		CTX_LOCK(ctx);