Re: [PATCH] pxa168_eth: fix mdiobus_scan() error check

[Sergei Shtylyov]

On 05/01/2016 11:25 PM, Sergei Shtylyov wrote:

Since mdiobus_scan() returns either an error code or NULL on error, the
driver should check  for both,  not only for NULL, otherwise a crash is
imminent...
Reported-by: Arnd Bergmann <a...@arndb.de>
Signed-off-by: Sergei Shtylyov <sergei.shtyl...@cogentembedded.com>

---
The patch is against DaveM's 'net.git' repo.

  drivers/net/ethernet/marvell/pxa168_eth.c |    2 ++
  1 file changed, 2 insertions(+)

Index: net/drivers/net/ethernet/marvell/pxa168_eth.c
===================================================================
--- net.orig/drivers/net/ethernet/marvell/pxa168_eth.c
+++ net/drivers/net/ethernet/marvell/pxa168_eth.c
@@ -979,6 +979,8 @@ static int pxa168_init_phy(struct net_de
          return 0;

      pep->phy = mdiobus_scan(pep->smi_bus, pep->phy_addr);
+    if (IS_ERR(pep->phy))
+        return PTR_ERR(pep->phy);
      if (!pep->phy)
          return -ENODEV;

Should not this check be removed too and

    That's my next move -- for now I'm fixing the existing bug in this driver
only.

   In fact, it can't be removed yet as mdiobus_scan() may return NULL on 
other error path. There's certainly a space for improvements yet...
[...]

MBR, Sergei