lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 2 Jun 2022 19:46:22 -0700 From: Jakub Kicinski <kuba@...nel.org> To: Kaarel Pärtel <kaarelp2rtel@...il.com> Cc: Wolfgang Grandegger <wg@...ndegger.com>, Marc Kleine-Budde <mkl@...gutronix.de>, "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, Paolo Abeni <pabeni@...hat.com>, linux-can@...r.kernel.org, netdev@...r.kernel.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH] net: add operstate for vcan and dummy On Thu, 2 Jun 2022 11:19:29 +0300 Kaarel Pärtel wrote: > The idea here is simple. The vcan and the dummy network devices > currently do not set the operational state of the interface. > The result is that the interface state will be UNKNOWN. > > The kernel considers the unknown state to be the same as up: > https://elixir.bootlin.com/linux/latest/source/include/linux/netdevice.h#L4125 > > However for users this creates confusion: > https://serverfault.com/questions/629676/dummy-network-interface-in-linux > > The change in this patch is very simple. When the interface is set up, the > operational state is set to IF_OPER_UP. > > Signed-off-by: Kaarel Pärtel <kaarelp2rtel@...il.com> You can change the carrier state from user space on a dummy device, that will inform the kernel of the operstate: # ip link add type dummy # ip link show dev dummy0 8: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 8e:35:15:22:e3:d7 brd ff:ff:ff:ff:ff:ff # ip link set dev dummy0 up # ip link show dev dummy0 8: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000 link/ether 8e:35:15:22:e3:d7 brd ff:ff:ff:ff:ff:ff # ip link set dev dummy0 carrier off # ip link set dev dummy0 carrier on # ip link show dev dummy0 8: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 8e:35:15:22:e3:d7 brd ff:ff:ff:ff:ff:ff Flipping all soft devices which don't have a lower or don't expect user space management to UP is fine but doing it one by one feels icky. Yet another random thing a driver author has to know to flip. If people are confused about seeing UNKNOWN in ip link output maybe we should move displaying that under the -d flag (detailed output)? Saves space, and nobody will get confused.
Powered by blists - more mailing lists