Trying not to burn my house down

I want to set up an Ethernet cable straight from my router in the laundry to my bedroom going through the roof / attic space, I estimate it’ll take about 20 - 30 metres of cable.

I was gonna just put a hole in my roof then just chuck it in but my old man brought up the fire concerns with it being such a long cord, I’ve tried looking up the fire and safety regulations on the internet, but that didn’t particularly help, so I was hoping I could get answers from reddit.

Just to be clear I do not intend on setting it up through a patch panel, just straight cord from router to pc. I’m also looking to use cat6 Ethernet cables and am wondering if that’s gonna matter in regards to fire safety.

Edit: A massive thanks to everyone who left a word of advise, it was a great insight as to what I could’ve done but it was brought to my attention by someone that in Australia it is illegal to do your own cabling in concealed space which include the roof and could lead to fine from $1,300 up to $13,000, meanwhile getting a licenced cabler should only cost around $200 - $300, which is a cost of much rather pay, once again thanks to all who helped out, much appreciated