linux-hardening - Re: [PATCH v5 2/6] mm/slab: Plumb kmem_buckets into __do_kmalloc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <e42cb34b-f482-4232-81e3-4dab8a171d34@suse.cz>
Date: Thu, 20 Jun 2024 22:44:16 +0200
From: Vlastimil Babka <vbabka@...e.cz>
To: Kees Cook <kees@...nel.org>
Cc: "GONG, Ruiqi" <gongruiqi@...weicloud.com>,
 Christoph Lameter <cl@...ux.com>, Pekka Enberg <penberg@...nel.org>,
 David Rientjes <rientjes@...gle.com>, Joonsoo Kim <iamjoonsoo.kim@....com>,
 jvoisin <julien.voisin@...tri.org>, Andrew Morton
 <akpm@...ux-foundation.org>, Roman Gushchin <roman.gushchin@...ux.dev>,
 Hyeonggon Yoo <42.hyeyoo@...il.com>, Xiu Jianfeng <xiujianfeng@...wei.com>,
 Suren Baghdasaryan <surenb@...gle.com>,
 Kent Overstreet <kent.overstreet@...ux.dev>, Jann Horn <jannh@...gle.com>,
 Matteo Rizzo <matteorizzo@...gle.com>, Thomas Graf <tgraf@...g.ch>,
 Herbert Xu <herbert@...dor.apana.org.au>, linux-kernel@...r.kernel.org,
 linux-mm@...ck.org, linux-hardening@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [PATCH v5 2/6] mm/slab: Plumb kmem_buckets into
 __do_kmalloc_node()

On 6/20/24 8:46 PM, Kees Cook wrote:
> On Thu, Jun 20, 2024 at 03:37:31PM +0200, Vlastimil Babka wrote:
>> On 6/20/24 3:08 PM, Vlastimil Babka wrote:
>> > On 6/19/24 9:33 PM, Kees Cook wrote:
>> > I was wondering why I don't see the buckets in slabinfo and turns out it was
>> > SLAB_MERGE_DEFAULT. It would probably make sense for SLAB_MERGE_DEFAULT to
>> > depends on !SLAB_BUCKETS now as the merging defeats the purpose, wdyt?
>> 
>> Hm I might have been just blind, can see them there now. Anyway it probably
>> doesn't make much sense to have SLAB_BUCKETS and/or RANDOM_KMALLOC_CACHES
>> together with SLAB_MERGE_DEFAULT?
> 
> It's already handled so that the _other_ caches can still be merged if
> people want it. See new_kmalloc_cache():
> 
> #ifdef CONFIG_RANDOM_KMALLOC_CACHES
>         if (type >= KMALLOC_RANDOM_START && type <= KMALLOC_RANDOM_END)
>                 flags |= SLAB_NO_MERGE;
> #endif

OK