Do I need to watch the anime or read the manga before seeing the 2017 movie?

I don't think that you need to watch or read any of the previous material in order to understand the new 2017 movie. That being said, the subject matter is pretty convoluted to begin with. I had to watch the original 1995 (?) anime several times before I properly wrapped my head around everything that was going on.

(Even now I'm not 100% convinced that I've got it all...)

This is to say that you might very well walk out of the 2017 movie going "what the heck was going on there?!" whether or not you are familiar with the original source material. Assuming that Hollywood hasn't dumbed it all down to the point where a trained chimpanzee could follow the plot, that is.

(Which is a very real concern I have with the new movie.)

I would also echo the suggestion that you should seek out and watch the previous anime in this franchise - either before or after watching the 2017 movie - as it is a good watch regardless.

tl;dr: You don't need to be familiar with the source material, though I highly recommend watching them.

Long Version

First things first, early reviews of the movie seem to indicate that it does not share it's source materiel's narrative and thematic focus, and ends up being a fairly generic sci-fi action flick. Of course I've not seen the movie yet, but I don't think it will really count as part of the franchise.

That said, I don't think its narrative competence matters anyway. Ghost in the Shell's animated entries are spread across 3 separate "continuities," as I like to call them. Basically, they are 3 different storylines that share the same setting characters, and (to some extent) themes, but tell entirely different stories:

1. The original '95 Ghost in the Shell movie and it's sequel, Innocence.
2. The Ghost in the Shell: Stand Alone Complex TV show, it's sequel TV show 2nd Gig, and the sequel movie Solid State Society. (There's also a Laughing Man compilation movie which condenses the core plot of the first show.)
3. The series of short movies entitled Ghost in the Shell: Arise. These are less about philosophy and more about political suspense/thrills.

What this means is that any of them will introduce you to the same characters and settings, but they will be alternate versions of them. The focus and style of each continuity is different from each other. The movie, from what I understand, is partly its own continuity and partly an adaptation of the '95 movie. That said, I'd need to see it first to say for sure.

It's not a precise remake, and it will undoubtedly take some liberties, but in all I would say "not to enjoy the stand alone movie".

To this I would add: Do see it. Just for the joy that is watching a very good anime. Also, hunt down Stand Alone Complex and watch that (it's a TV series). It expands on some things, and gives different stories in the same universe with the same characters. It's worth the watching if you like the type of movie.

Always read the manga before watching anything animated. I have learned that manga and books always give an extra context and significance to animes and the movies to follow. Plus it pays respect to the creators.