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Subject: Re: kernel BUG at net/core/net-sysfs.c:LINE!
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        syzbot <syzbot+6024817a931b2830bc93@syzkaller.appspotmail.com>
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 <20190323171621.GF9224@smile.fi.intel.com>
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thanks , Can it be fixed like this?

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 4ff661f..e609c8d 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -1745,16 +1745,21 @@ int netdev_register_kobject(struct net_device *ndev)

         error = device_add(dev);
         if (error)
-               return error;
+               goto error_put_device;

         error = register_queue_kobjects(ndev);
-       if (error) {
-               device_del(dev);
-               return error;
-       }
+       if (error)
+               goto error_device_del;

         pm_runtime_set_memalloc_noio(dev, true);

+       return 0;
+
+error_device_del:
+       device_del(dev);
+error_put_device:
+       ndev->reg_state = NETREG_RELEASED;
+       put_device(dev);
         return error;
  }

在 2019/3/24 1:16, Andy Shevchenko 写道:
> Nice.
>
> I looked briefly in the flow of this report and it looks like the patch above
> should be reverted.
>
> The problem is not so easy to fix. One approach is to initialize device
> (and thus kobject) somewhere in alloc_netdev() and put device in free_netdev()
> respectively, but this might produce more interesting regressions.