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Date:   Fri, 18 Nov 2022 09:11:07 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Andrey Konovalov <andreyknvl@gmail.com>,
        Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        linux-mm@kvack.org, kasan-dev@googlegroups.com,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2] mm: Make ksize() a reporting-only function
Message-ID: <202211180907.A4C218F@keescook>
References: <20221118035656.gonna.698-kees@kernel.org>
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On Fri, Nov 18, 2022 at 11:32:36AM +0100, Vlastimil Babka wrote:
> On 11/18/22 04:56, Kees Cook wrote:
> > With all "silently resizing" callers of ksize() refactored, remove the
> 
> At cursory look seems it's true now in -next (but not mainline?) can you
> confirm?

Almost, yes. I realized there is 1 case in the BPF verifier that
remains. (I thought it was picked up, but only a prereq patch was.) I'm
going to resend that one today, but I would expect it to be picked
up soon. (But, yes, definitely not for mainline.)

> That would probably be safe enough to have slab.git expose this to -next now
> and time a PR appropriately in the next merge window?

Possibly. I suspect syzkaller might trip KASAN on any larger BPF tests
until I get the last one landed. And if you don't want to do the timing
of the PR, I can carry this patch in my hardening tree, since I already
have to do a two-part early/late-merge-window PR there.

-- 
Kees Cook