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Date:   Sun, 12 Nov 2023 14:03:19 -0500
From:   "Theodore Ts'o" <tytso@mit.edu>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Jasper Niebuhr <yjnworkstation@gmail.com>,
        Willy Tarreau <w@1wt.eu>, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org
Subject: Re: [PATCH] exitz syscall
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On Sun, Nov 12, 2023 at 10:50:10AM -0800, Linus Torvalds wrote:
> 
> However, it still needs to also make sure that the memory in question
> is not file-backed etc. Which the patch I saw didn't seem to do
> either.

Well, yes.  If the program isn't using a small amount of anonymous
memory, which is also mlock'ed so it doesn't get written to swap, the
rest of it is a total waste of time.

And from what I've seen from the O_PONIES debate (e.g., users
truncating files and rewriting them, and then complaining when the
top-ten score file disappears after the system crashes when they close
the OpenGL connection to the proprietary kernel driver), my basic
assumption is that anything application writers will get wrong, they
probably will....

     	      		  	       - Ted