firewire: fix memory leak of fw_request instances

Found and debugged by Jay Fenlason <fenlason@redhat.com>.
The bug was especially noticeable with direct I/O over fw-sbp2.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>

diff --git a/drivers/firewire/fw-transaction.c b/drivers/firewire/fw-transaction.c
index c4b3417..3ce8e2f 100644 (file)
--- a/drivers/firewire/fw-transaction.c
+++ b/drivers/firewire/fw-transaction.c
@@ -605,8 +605,10 @@ fw_send_response(struct fw_card *card, struct fw_request *request, int rcode)
         * check is sufficient to ensure we don't send response to
         * broadcast packets or posted writes.
         */
-       if (request->ack != ACK_PENDING)
+       if (request->ack != ACK_PENDING) {
+               kfree(request);
                return;
+       }
 
        if (rcode == RCODE_COMPLETE)
                fw_fill_response(&request->response, request->request_header,

diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h
index 5abed19..5ceaccd 100644 (file)
--- a/drivers/firewire/fw-transaction.h
+++ b/drivers/firewire/fw-transaction.h
@@ -123,6 +123,10 @@ typedef void (*fw_transaction_callback_t)(struct fw_card *card, int rcode,
                                          size_t length,
                                          void *callback_data);
 
+/*
+ * Important note:  The callback must guarantee that either fw_send_response()
+ * or kfree() is called on the @request.
+ */
 typedef void (*fw_address_callback_t)(struct fw_card *card,
                                      struct fw_request *request,
                                      int tcode, int destination, int source,