Re: [PATCH v2] proc: allow restricting /proc/pid/mem writes

From: Kees Cook
Date: Mon Mar 04 2024 - 12:56:17 EST


On Mon, Mar 04, 2024 at 02:35:29PM +0000, Adrian Ratiu wrote:
> Yes, easy to block and also respect page permissions (can't write
> read-only memory) as well as require ptrace access anyway by checking
> PTRACE_MODE_ATTACH_REALCREDS.

right, I don't think process_vm_writev() ignores page permissions? i.e. I
don't see where it is using FOLL_FORCE, which is one of the central
problems with /proc/$pid/mem. (Which reminds me, this is worth mentioning
more explicitly in the commit log for v3.)

--
Kees Cook