Re: [PATCH] net: via-rhine: net: Fix a resource leak in rhine_init()

From: Jia-Ju Bai
Date: Fri May 03 2019 - 23:58:17 EST

On 2019/5/4 11:41, David Miller wrote:
From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
Date: Sat, 4 May 2019 11:23:06 +0800

On 2019/5/4 11:13, David Miller wrote:
From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
Date: Sat, 4 May 2019 11:08:13 +0800

When platform_driver_register() fails, pci_unregister_driver() is not
called to release the resource allocated by pci_register_driver().

To fix this bug, error handling code for platform_driver_register()
pci_register_driver() is separately implemented.

This bug is found by a runtime fuzzing tool named FIZZER written by

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
I think the idea here is that PCI is not enabled in the kernel, it is
fine for the pci register to fail and only the platform register to

You are breaking that.
Okay, I can understand it.
If so, I think that platform_driver_register() should be called before
pci_register_driver(), and it is still necessary to separately handle
their errors.
If you agree, I will send a v2 patch.
It is only a failure if both fail.

If at least one succeeds, the driver can potentially probe properly.

Thanks for the explanation, I understand now :)
The code logic seems a little strange, but it should be correct in rhine_init()...
If so, if one fails, I wonder whether it is correct for rhine_cleanup() to call both platform_driver_unregister() and pci_unregister_driver()?

Best wishes,
Jia-Ju Bai