Re: [PATCH net] netrom: do some basic forms of validation on incoming frames

From: jj

Date: Fri Apr 10 2026 - 11:49:24 EST

This is NOT an obsolete protocol..this is in use by amateur radio operators world-wide...we use it for RF comms usually, because what happens if the internet goes "down", we can still provide comms over slower RF links....(plus it's a fun mode)please PLEASE do not drop...and sorry for the noise...

de John VE1JOT

On 2026-04-10 07:28, Simon Horman wrote:
On Fri, Apr 10, 2026 at 07:24:36AM +0200, Greg Kroah-Hartman wrote:
On Thu, Apr 09, 2026 at 08:32:35PM -0700, Jakub Kicinski wrote:
On Thu, 9 Apr 2026 20:03:28 +0100 Simon Horman wrote:
I expect that checking skb->len isn't sufficient here
and pskb_may_pull needs to be used to ensure that
the data is also available in the linear section of the skb.
Or for simplicity we could also be testing against skb_headlen()
since we don't expect any legit non-linear frames here? Dunno.
Sure, that's find by me if it leads to simpler code than
using pskb_may_pull(). Else I'd lean towards pskb_may_pull()
as it is a more general approach that feels worth proliferating.

I'll be glad to change this either way, your call. Given that this is
an obsolete protocol that seems to only be a target for drive-by fuzzers
to attack, whatever the simplest thing to do to quiet them up I'll be
glad to implement.

Or can we just delete this stuff entirely? :)
Deleting sounds good to me.
But we likely need a deprecation process.
In which case fixing these bugs still makes sense for the short term.