3c505: do not set pcb->data.raw beyond its size

Ensure that we do not set pcb->data.raw beyond its size, print an error message
and return false if we attempt to. A timout message was printed one too early.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/3c505.c b/drivers/net/3c505.c
index 6124605bef05404bb2dee77114d5f8fcd1a1aff8..a8107f992fb4b03a243287ecadf879dbc21e024d 100644 (file)
--- a/drivers/net/3c505.c
+++ b/drivers/net/3c505.c
@@ -493,21 +493,27 @@ static bool receive_pcb(struct net_device *dev, pcb_struct * pcb)
        }
        /* read the data */
        spin_lock_irqsave(&adapter->lock, flags);
-       i = 0;
-       do {
-               j = 0;
-               while (((stat = get_status(dev->base_addr)) & ACRF) == 0 && j++ < 20000);
-               pcb->data.raw[i++] = inb_command(dev->base_addr);
-               if (i > MAX_PCB_DATA)
-                       INVALID_PCB_MSG(i);
-       } while ((stat & ASF_PCB_MASK) != ASF_PCB_END && j < 20000);
+       for (i = 0; i < MAX_PCB_DATA; i++) {
+               for (j = 0; j < 20000; j++) {
+                       stat = get_status(dev->base_addr);
+                       if (stat & ACRF)
+                               break;
+               }
+               pcb->data.raw[i] = inb_command(dev->base_addr);
+               if ((stat & ASF_PCB_MASK) == ASF_PCB_END || j >= 20000)
+                       break;
+       }
        spin_unlock_irqrestore(&adapter->lock, flags);
+       if (i >= MAX_PCB_DATA) {
+               INVALID_PCB_MSG(i);
+               return false;
+       }
        if (j >= 20000) {
                TIMEOUT_MSG(__LINE__);
                return false;
        }
-       /* woops, the last "data" byte was really the length! */
-       total_length = pcb->data.raw[--i];
+       /* the last "data" byte was really the length! */
+       total_length = pcb->data.raw[i];
 
        /* safety check total length vs data length */
        if (total_length != (pcb->length + 2)) {