Fix a broken size check in the pvr input plugin (ref. CVE-2008-5239).

1 files changed, 6 insertions, 4 deletions

diff --git a/src/input/input_pvr.c b/src/input/input_pvr.c
index 18d29f6be..5238fccbc 100644
--- a/src/input/input_pvr.c
+++ b/src/input/input_pvr.c
@@ -1202,14 +1202,17 @@ static buf_element_t *pvr_plugin_read_block (input_plugin_t *this_gen, fifo_buff
   buf_element_t        *buf;
   int                   speed = _x_get_speed(this->stream);
 
-  if (todo < 0 || todo > buf->size)
-    return NULL;
-
   if( !this->pvr_running ) {
     xprintf(this->stream->xine, XINE_VERBOSITY_DEBUG, "input_pvr: thread died, aborting\n");
     return NULL;  
   }
 
+  buf = fifo->buffer_pool_alloc (fifo);
+  if (todo < 0 || todo > buf->size) {
+    buf->free_buffer(buf);
+    return NULL;
+  }
+
   if( this->scr_tunning == -2 )
     speed = this->speed_before_pause;
 
@@ -1233,7 +1236,6 @@ static buf_element_t *pvr_plugin_read_block (input_plugin_t *this_gen, fifo_buff
 
   pvr_event_handler(this);
   
-  buf = fifo->buffer_pool_alloc (fifo);
   buf->content = buf->mem;
     
   pthread_mutex_lock(&this->lock);