[PATCH] netpoll fix racy dev->flags usage

[Matt Mackall <mpm@xxxxxxxxxxx>]

Put ndev->flags usage under the lock. Spotted by Patrick McHardy.

Signed-off-by: Matt Mackall <mpm@xxxxxxxxxxx>

Index: np/net/core/netpoll.c
===================================================================
--- np.orig/net/core/netpoll.c  2005-03-10 17:02:03.000000000 -0600
+++ np/net/core/netpoll.c       2005-03-10 17:12:46.000000000 -0600
@@ -632,16 +632,13 @@ int netpoll_setup(struct netpoll *np)
        }
 
        if (!netif_running(ndev)) {
-               unsigned short oflags;
                unsigned long atmost, atleast;
 
                printk(KERN_INFO "%s: device %s not up yet, forcing it\n",
                       np->name, np->dev_name);
 
-               oflags = ndev->flags;
-
                rtnl_shlock();
-               if (dev_change_flags(ndev, oflags | IFF_UP) < 0) {
+               if (dev_change_flags(ndev, ndev->flags | IFF_UP) < 0) {
                        printk(KERN_ERR "%s: failed to open %s\n",
                               np->name, np->dev_name);
                        rtnl_shunlock();

-- 
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