82596: do not panic on out of memory

If dev_alloc_skb() failed then free already allocated skbs.
remove_rx_bufs() can be called multiple times, so set rbd->skb to NULL
to avoid double free. remove_rx_bufs() was moved upwards to be seen by
init_rx_bufs().

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/82596.c b/drivers/net/82596.c
index dd8dc15..73073d0 100644 (file)
--- a/drivers/net/82596.c
+++ b/drivers/net/82596.c
@@ -525,7 +525,21 @@ static irqreturn_t i596_error(int irq, void *dev_id)
 }
 #endif
 
-static inline void init_rx_bufs(struct net_device *dev)
+static inline void remove_rx_bufs(struct net_device *dev)
+{
+       struct i596_private *lp = dev->ml_priv;
+       struct i596_rbd *rbd;
+       int i;
+
+       for (i = 0, rbd = lp->rbds; i < rx_ring_size; i++, rbd++) {
+               if (rbd->skb == NULL)
+                       break;
+               dev_kfree_skb(rbd->skb);
+               rbd->skb = NULL;
+       }
+}
+
+static inline int init_rx_bufs(struct net_device *dev)
 {
        struct i596_private *lp = dev->ml_priv;
        int i;
@@ -537,8 +551,11 @@ static inline void init_rx_bufs(struct net_device *dev)
        for (i = 0, rbd = lp->rbds; i < rx_ring_size; i++, rbd++) {
                struct sk_buff *skb = dev_alloc_skb(PKT_BUF_SZ);
 
-               if (skb == NULL)
-                       panic("82596: alloc_skb() failed");
+               if (skb == NULL) {
+                       remove_rx_bufs(dev);
+                       return -ENOMEM;
+               }
+
                skb->dev = dev;
                rbd->v_next = rbd+1;
                rbd->b_next = WSWAPrbd(virt_to_bus(rbd+1));
@@ -574,19 +591,8 @@ static inline void init_rx_bufs(struct net_device *dev)
        rfd->v_next = lp->rfds;
        rfd->b_next = WSWAPrfd(virt_to_bus(lp->rfds));
        rfd->cmd = CMD_EOL|CMD_FLEX;
-}
-
-static inline void remove_rx_bufs(struct net_device *dev)
-{
-       struct i596_private *lp = dev->ml_priv;
-       struct i596_rbd *rbd;
-       int i;
 
-       for (i = 0, rbd = lp->rbds; i < rx_ring_size; i++, rbd++) {
-               if (rbd->skb == NULL)
-                       break;
-               dev_kfree_skb(rbd->skb);
-       }
+       return 0;
 }
 
 
@@ -1013,7 +1019,11 @@ static int i596_open(struct net_device *dev)
                        return -EAGAIN;
        }
 #endif
-       init_rx_bufs(dev);
+       res = init_rx_bufs(dev);
+       if (res) {
+               free_irq(dev->irq, dev);
+               return res;
+       }
 
        netif_start_queue(dev);