e100: Fix broken cbs accounting due to missing memset.

Alan Stern noticed that e100 caused slab corruption.
commit 98468efddb101f8a29af974101c17ba513b07be1 changed
the allocation of cbs to use dma pools that don't return zeroed memory,
especially the cb->status field used to track which cb to clean, causing
(the visible) double freeing of skbs and a wrong free cbs count.

Now the cbs are explicitly zeroed at allocation time.

Reported-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Roger Oksanen <roger.oksanen@cs.helsinki.fi>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/e100.c b/drivers/net/e100.c
index 929701ca07d31bf1aedbcb7e54a9ba93bc6db654..839fb2b136d37bd9993cbfe42d44ddcffec90e2c 100644 (file)
--- a/drivers/net/e100.c
+++ b/drivers/net/e100.c
@@ -1829,6 +1829,7 @@ static int e100_alloc_cbs(struct nic *nic)
                                  &nic->cbs_dma_addr);
        if (!nic->cbs)
                return -ENOMEM;
+       memset(nic->cbs, 0, count * sizeof(struct cb));
 
        for (cb = nic->cbs, i = 0; i < count; cb++, i++) {
                cb->next = (i + 1 < count) ? cb + 1 : nic->cbs;
@@ -1837,7 +1838,6 @@ static int e100_alloc_cbs(struct nic *nic)
                cb->dma_addr = nic->cbs_dma_addr + i * sizeof(struct cb);
                cb->link = cpu_to_le32(nic->cbs_dma_addr +
                        ((i+1) % count) * sizeof(struct cb));
-               cb->skb = NULL;
        }
 
        nic->cb_to_use = nic->cb_to_send = nic->cb_to_clean = nic->cbs;