firewire: Fix the range check for the queue_iso payload pointer.

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

1 files changed, 5 insertions, 5 deletions

diff --git a/drivers/firewire/fw-device-cdev.c b/drivers/firewire/fw-device-cdev.c
index d02dbc5af91e..fab6dfbcca1b 100644
--- a/drivers/firewire/fw-device-cdev.c
+++ b/drivers/firewire/fw-device-cdev.c
@@ -711,7 +711,7 @@ static int ioctl_queue_iso(struct client *client, void __user *arg)
         struct fw_cdev_queue_iso request;
         struct fw_cdev_iso_packet __user *p, *end, *next;
         struct fw_iso_context *ctx = client->iso_context;
-        unsigned long payload, payload_end, header_length;
+        unsigned long payload, buffer_end, header_length;
         int count;
         struct {
                 struct fw_iso_packet packet;
@@ -732,11 +732,11 @@ static int ioctl_queue_iso(struct client *client, void __user *arg)
          * and the request.data pointer is ignored.*/
 
         payload = (unsigned long)request.data - client->vm_start;
-        payload_end = payload + (client->buffer.page_count << PAGE_SHIFT);
+        buffer_end = client->buffer.page_count << PAGE_SHIFT;
         if (request.data == 0 || client->buffer.pages == NULL ||
-            payload >= payload_end) {
+            payload >= buffer_end) {
                 payload = 0;
-                payload_end = 0;
+                buffer_end = 0;
         }
 
         if (!access_ok(VERIFY_READ, request.packets, request.size))
@@ -773,7 +773,7 @@ static int ioctl_queue_iso(struct client *client, void __user *arg)
                 if (u.packet.skip && ctx->type == FW_ISO_CONTEXT_TRANSMIT &&
                     u.packet.header_length + u.packet.payload_length > 0)
                         return -EINVAL;
-                if (payload + u.packet.payload_length > payload_end)
+                if (payload + u.packet.payload_length > buffer_end)
                         return -EINVAL;
 
                 if (fw_iso_context_queue(ctx, &u.packet,