On 2021/2/5 下午4:19, Marc Kleine-Budde wrote:

On 05.02.2021 15:25:59, Xulin Sun wrote:

quoted

If the previous can_net device has been successfully allocated, its
private data structure is impossible to be empty, remove this redundant
error return judgment. Otherwise, memory leaks for alloc_candev() will
be triggered.

Your analysis is correct, the netdev_priv() will never fail. But how
will this trigger a mem leak on alloc_candev()? I've removed that

Hi Marc,

The previous code judges the netdev_priv is empty, and then goto out. 
The correct approach should add free_candev(net_dev) before goto.

The code Like:

         class_dev = netdev_priv(net_dev);
         if (!class_dev) {
                 dev_err(dev, "Failed to init netdev cdevate");
+               free_candev(net_dev);
                 goto out;
         }

Otherwise, memory leaks for alloc_candev() will be triggered.

Now directly remove the impossible error return judgment to resolve the above possible issue.

Thanks

Xulin

statement. I'll add it back, if I've missed something.

quoted

Signed-off-by: Xulin Sun <redacted>

Applied to linux-can-next/testing.

Thanks,
Marc