Oct 05 2012

drivers/net/ethernet/amd/au1000_eth.c: fix error return code 

Author: Peter Senna Tschudin <peter.senna@gmail.com>

The function au1000_probe() return 0 for success and negative value
for most of its internal tests failures. There are exceptions
that are error cases going to err_out:. For this cases, the
function abort its success execution path, but returns non negative
value, making it dificult for a caller function to notice the error.

This patch fixes the error cases that do not return negative values.

This was found by Coccinelle, but the code change was made by hand.
This patch is not robot generated.

A simplified version of the semantic match that finds this problem is
as follows: (http://coccinelle.lip6.fr/)

// 
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// 

Signed-off-by: Peter Senna Tschudin 
Signed-off-by: David S. Miller 

---
 drivers/net/ethernet/amd/au1000_eth.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
 
diff --git a/drivers/net/ethernet/amd/au1000_eth.c b/drivers/net/ethernet/amd/au1000_eth.c
index 397596b..f195acf 100644
--- a/drivers/net/ethernet/amd/au1000_eth.c
+++ b/drivers/net/ethernet/amd/au1000_eth.c
@@ -1174,8 +1174,10 @@ static int __devinit au1000_probe(struct platform_device *pdev)
 	snprintf(aup->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
 		pdev->name, aup->mac_id);
 	aup->mii_bus->irq = kmalloc(sizeof(int)*PHY_MAX_ADDR, GFP_KERNEL);
-	if (aup->mii_bus->irq == NULL)
+	if (aup->mii_bus->irq == NULL) {
+		err = -ENOMEM;
 		goto err_out;
+	}
 
 	for (i = 0; i < PHY_MAX_ADDR; ++i)
 		aup->mii_bus->irq[i] = PHY_POLL;
@@ -1190,7 +1192,8 @@ static int __devinit au1000_probe(struct platform_device *pdev)
 		goto err_mdiobus_reg;
 	}
 
-	if (au1000_mii_probe(dev) != 0)
+	err = au1000_mii_probe(dev);
+	if (err != 0)
 		goto err_out;
 
 	pDBfree = NULL;
@@ -1205,6 +1208,7 @@ static int __devinit au1000_probe(struct platform_device *pdev)
 	}
 	aup->pDBfree = pDBfree;
 
+	err = -ENODEV;
 	for (i = 0; i < NUM_RX_DMA; i++) {
 		pDB = au1000_GetFreeDB(aup);
 		if (!pDB)
@@ -1213,6 +1217,8 @@ static int __devinit au1000_probe(struct platform_device *pdev)
 		aup->rx_dma_ring[i]->buff_stat = (unsigned)pDB->dma_addr;
 		aup->rx_db_inuse[i] = pDB;
 	}
+
+	err = -ENODEV;
 	for (i = 0; i < NUM_TX_DMA; i++) {
 		pDB = au1000_GetFreeDB(aup);
 		if (!pDB)

qlambert