Re: Off-by-one error in net/8021q/vlan.c

Le mercredi 16 février 2011 à 08:28 -0800, Phil Karn a écrit :

On 2/16/11 8:10 AM, richard -rw- weinberger wrote:

quoted

On Wed, Feb 16, 2011 at 4:58 PM, Phil Karn [off-list ref] wrote:

quoted

On 2/16/11 4:51 AM, richard -rw- weinberger wrote:

quoted

On Wed, Feb 16, 2011 at 11:58 AM, Phil Karn [off-list ref] wrote:

quoted

The range check on vlan_id in register_vlan_device is off by one, and it
prevents the creation of a vlan interface for vlan ID 4095. (OSX allows
this, I checked.)

Then OSX should fix their code. 4095 is reserved.

If it's reserved, then it's up to the user to reserve it.

No.

See:
http://standards.ieee.org/getieee802/download/802.1Q-2005.pdf

Well, then I guess we all know better than the user. That's the Windows
Way...no, wait, I thought this is Linux.

The fact is that I did encounter a misconfigured switch using vlan 4095,
and because of this off-by-one error I was unable to talk to it and fix it.

I was hoping I wouldn't have to patch every new kernel I install.

You can use an OSX gateway ;)

If we allow ID 4095, then some users will complain we violate rules.

Really you cannot push this patch in official kernel only to ease your
life ;)