Yeah, the security implications are obvious, R+W+X should not be used with untrusted inputs. Not that I'd recommend this, but alternatively you could also map

Yeah, the security implications are obvious, R+W+X should not be used with untrusted inputs. Not that I'd recommend this, but alternatively you could also map exact same memory twice, one with R+X and the other with R+W. The attacker would need to figure out the writable address. Unfortunately there are probably a lot of ways to accidentally leak this information to the attacker... There are still plenty of use cases where inputs can be trusted.