GTP-u in linux kernel

[jbdamiano]

Is your feature request related to a problem? Please describe. I'm working on GTP and I need to recompile the kernel for every release to activate the GTP in kernel I need to do add the GTP-u support in kernel

diff --git a/Microsoft/config-wsl b/Microsoft/config-wsl
index ab578e1c8891..b5de4c6a7fda 100644
--- a/Microsoft/config-wsl
+++ b/Microsoft/config-wsl
@@ -1840,7 +1840,7 @@ CONFIG_IPVTAP=y
 CONFIG_VXLAN=y
 CONFIG_GENEVE=y
 # CONFIG_BAREUDP is not set
-# CONFIG_GTP is not set
+CONFIG_GTP=y
 # CONFIG_MACSEC is not set
 # CONFIG_NETCONSOLE is not set
 CONFIG_TUN=y
    add the GTP-u support in kernel

diff --git a/Microsoft/config-wsl b/Microsoft/config-wsl
index ab578e1c8891..b5de4c6a7fda 100644
--- a/Microsoft/config-wsl
+++ b/Microsoft/config-wsl
@@ -1840,7 +1840,7 @@ CONFIG_IPVTAP=y
 CONFIG_VXLAN=y
 CONFIG_GENEVE=y
 # CONFIG_BAREUDP is not set
-# CONFIG_GTP is not set
+CONFIG_GTP=y
 # CONFIG_MACSEC is not set
 # CONFIG_NETCONSOLE is not set
 CONFIG_TUN=y

Is it possible to enable it by default ? I used it since 6 months without issue.

[benhillis]

@tyhicks - any concerns on your side about adding this config flag to the official kernel?

[tyhicks]

@benhillis I'm not real familiar with this module. At first glance, some potential negatives are:

• I'm guessing that it is not something that would be widely used. It would be nice if some other users spoke up and disproved my assumption here.
• A fraction of the WSL2 users will ever use GTP-u but, with the current limitation requiring that everything be built-in to the kernel, every user would have it enabled.
  • An additional attack surface is present with no way to denylist the module
  • An additional maintenance cost when flaws/bugs are found in GTP-u

The obvious positives are that @jbdamiano wouldn't have to do this manual (re)enablement work on every WSL2 kernel release and there would be no roadblocks for future users that come along wanting to use GTP-u.

[jbdamiano]

@tyhicks The GTP-u protocol is used to encapsulate the traffic from layer 3 in Telecom data plane layer. It's needed when you are working on Telecom node. In the kernel SCTP is activated and used also in Telecom node and I 'm guessing that it is not something that would be widely used except in Telecom business.

[jbdamiano]

With the 6.6.36.3 WSL2 from linux supports module, GTP could be activated as a module

[jbdamiano]

In addition, with this new kernel version, add the GTP in the kernel removed the module support.

[jbdamiano]

@benhillis @tyhicks I update this issue opened 2 years ago. Do I have to re-open a new one ?