From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B91DC43331 for ; Tue, 12 Nov 2019 07:18:21 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 66F982067B for ; Tue, 12 Nov 2019 07:18:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 66F982067B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17342-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 22371 invoked by uid 550); 12 Nov 2019 07:18:12 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 22345 invoked from network); 12 Nov 2019 07:18:12 -0000 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=am10xx8IfJqOSuDyYTDQaz4P8Dm7qQG6az4OEVbOtdA=; b=t1xU/Df3jNezEJGZQHb1rO/6RnRwb5RYBz9TbVHKhPmlj8ei6qZAj1aGQsX8w7/Q0n O2YiIy0kZEvDdyjqhA2qW1BzdyFgClXG0/A3BaBPqXBWp/ttC/u6ZqL+Swc5ZWOurLQf Me/3zNOuRiz0EfhUG08PvNMzcqsu9NKsKg9EaSCaYZiNDVdOqHMykoc/YZ83mtr6YEY9 GG4CMWJZEkZCfYmNeIVeQXYCs6YQngIjq0C90P6bgmZqqEUj66O6KauIyt/lN3qy+R+b V/hWq2QDBVxV/7eJMbytZ8vDlUHQuEJdZRFYTOL6r/6O1hx4lG/J14RFmkUJFhKaW9Jt jw1g== X-Gm-Message-State: APjAAAXpEYqv4vpeKtImGH11YLI/LdIuzEVYCaTwIcNRdI91qXZGbEnE UVOqPCqoDZb3rMEiBwo4108= X-Google-Smtp-Source: APXvYqz6F1V+0wJw6FjYWnIt+zbcmwGLE/0fVKGtteLeVQJqShnSZrFgTd7XIU7AThhvJJVgUhRZug== X-Received: by 2002:a05:600c:210b:: with SMTP id u11mr2576008wml.170.1573543080951; Mon, 11 Nov 2019 23:18:00 -0800 (PST) Subject: Re: [kernel-hardening] [PATCH 09/38] usercopy: Mark kmalloc caches as usercopy caches To: Kees Cook , linux-kernel@vger.kernel.org Cc: David Windsor , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , linux-mm@kvack.org, linux-xfs@vger.kernel.org, Linus Torvalds , Alexander Viro , Andy Lutomirski , Christoph Hellwig , Christoph Lameter , "David S. Miller" , Laura Abbott , Mark Rutland , "Martin K. Petersen" , Paolo Bonzini , Christian Borntraeger , Christoffer Dall , Dave Kleikamp , Jan Kara , Luis de Bethencourt , Marc Zyngier , Rik van Riel , Matthew Garrett , linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, kernel-hardening@lists.openwall.com, Vlastimil Babka , Michal Kubecek References: <1515636190-24061-1-git-send-email-keescook@chromium.org> <1515636190-24061-10-git-send-email-keescook@chromium.org> From: Jiri Slaby Autocrypt: addr=jslaby@suse.cz; prefer-encrypt=mutual; keydata= mQINBE6S54YBEACzzjLwDUbU5elY4GTg/NdotjA0jyyJtYI86wdKraekbNE0bC4zV+ryvH4j rrcDwGs6tFVrAHvdHeIdI07s1iIx5R/ndcHwt4fvI8CL5PzPmn5J+h0WERR5rFprRh6axhOk rSD5CwQl19fm4AJCS6A9GJtOoiLpWn2/IbogPc71jQVrupZYYx51rAaHZ0D2KYK/uhfc6neJ i0WqPlbtIlIrpvWxckucNu6ZwXjFY0f3qIRg3Vqh5QxPkojGsq9tXVFVLEkSVz6FoqCHrUTx wr+aw6qqQVgvT/McQtsI0S66uIkQjzPUrgAEtWUv76rM4ekqL9stHyvTGw0Fjsualwb0Gwdx ReTZzMgheAyoy/umIOKrSEpWouVoBt5FFSZUyjuDdlPPYyPav+hpI6ggmCTld3u2hyiHji2H cDpcLM2LMhlHBipu80s9anNeZhCANDhbC5E+NZmuwgzHBcan8WC7xsPXPaiZSIm7TKaVoOcL 9tE5aN3jQmIlrT7ZUX52Ff/hSdx/JKDP3YMNtt4B0cH6ejIjtqTd+Ge8sSttsnNM0CQUkXps w98jwz+Lxw/bKMr3NSnnFpUZaxwji3BC9vYyxKMAwNelBCHEgS/OAa3EJoTfuYOK6wT6nadm YqYjwYbZE5V/SwzMbpWu7Jwlvuwyfo5mh7w5iMfnZE+vHFwp/wARAQABtBtKaXJpIFNsYWJ5 IDxqc2xhYnlAc3VzZS5jej6JAjgEEwECACIFAk6S6NgCGwMGCwkIBwMCBhUIAgkKCwQWAgMB Ah4BAheAAAoJEL0lsQQGtHBJgDsP/j9wh0vzWXsOPO3rDpHjeC3BT5DKwjVN/KtP7uZttlkB duReCYMTZGzSrmK27QhCflZ7Tw0Naq4FtmQSH8dkqVFugirhlCOGSnDYiZAAubjTrNLTqf7e 5poQxE8mmniH/Asg4KufD9bpxSIi7gYIzaY3hqvYbVF1vYwaMTujojlixvesf0AFlE4x8WKs wpk43fmo0ZLcwObTnC3Hl1JBsPujCVY8t4E7zmLm7kOB+8EHaHiRZ4fFDWweuTzRDIJtVmrH LWvRDAYg+IH3SoxtdJe28xD9KoJw4jOX1URuzIU6dklQAnsKVqxz/rpp1+UVV6Ky6OBEFuoR 613qxHCFuPbkRdpKmHyE0UzmniJgMif3v0zm/+1A/VIxpyN74cgwxjhxhj/XZWN/LnFuER1W zTHcwaQNjq/I62AiPec5KgxtDeV+VllpKmFOtJ194nm9QM9oDSRBMzrG/2AY/6GgOdZ0+qe+ 4BpXyt8TmqkWHIsVpE7I5zVDgKE/YTyhDuqYUaWMoI19bUlBBUQfdgdgSKRMJX4vE72dl8BZ +/ONKWECTQ0hYntShkmdczcUEsWjtIwZvFOqgGDbev46skyakWyod6vSbOJtEHmEq04NegUD al3W7Y/FKSO8NqcfrsRNFWHZ3bZ2Q5X0tR6fc6gnZkNEtOm5fcWLY+NVz4HLaKrJuQINBE6S 54YBEADPnA1iy/lr3PXC4QNjl2f4DJruzW2Co37YdVMjrgXeXpiDvneEXxTNNlxUyLeDMcIQ K8obCkEHAOIkDZXZG8nr4mKzyloy040V0+XA9paVs6/ice5l+yJ1eSTs9UKvj/pyVmCAY1Co SNN7sfPaefAmIpduGacp9heXF+1Pop2PJSSAcCzwZ3PWdAJ/w1Z1Dg/tMCHGFZ2QCg4iFzg5 Bqk4N34WcG24vigIbRzxTNnxsNlU1H+tiB81fngUp2pszzgXNV7CWCkaNxRzXi7kvH+MFHu2 1m/TuujzxSv0ZHqjV+mpJBQX/VX62da0xCgMidrqn9RCNaJWJxDZOPtNCAWvgWrxkPFFvXRl t52z637jleVFL257EkMI+u6UnawUKopa+Tf+R/c+1Qg0NHYbiTbbw0pU39olBQaoJN7JpZ99 T1GIlT6zD9FeI2tIvarTv0wdNa0308l00bas+d6juXRrGIpYiTuWlJofLMFaaLYCuP+e4d8x rGlzvTxoJ5wHanilSE2hUy2NSEoPj7W+CqJYojo6wTJkFEiVbZFFzKwjAnrjwxh6O9/V3O+Z XB5RrjN8hAf/4bSo8qa2y3i39cuMT8k3nhec4P9M7UWTSmYnIBJsclDQRx5wSh0Mc9Y/psx9 B42WbV4xrtiiydfBtO6tH6c9mT5Ng+d1sN/VTSPyfQARAQABiQIfBBgBAgAJBQJOkueGAhsM AAoJEL0lsQQGtHBJN7UQAIDvgxaW8iGuEZZ36XFtewH56WYvVUefs6+Pep9ox/9ZXcETv0vk DUgPKnQAajG/ViOATWqADYHINAEuNvTKtLWmlipAI5JBgE+5g9UOT4i69OmP/is3a/dHlFZ3 qjNk1EEGyvioeycJhla0RjakKw5PoETbypxsBTXk5EyrSdD/I2Hez9YGW/RcI/WC8Y4Z/7FS ITZhASwaCOzy/vX2yC6iTx4AMFt+a6Z6uH/xGE8pG5NbGtd02r+m7SfuEDoG3Hs1iMGecPyV XxCVvSV6dwRQFc0UOZ1a6ywwCWfGOYqFnJvfSbUiCMV8bfRSWhnNQYLIuSv/nckyi8CzCYIg c21cfBvnwiSfWLZTTj1oWyj5a0PPgGOdgGoIvVjYXul3yXYeYOqbYjiC5t99JpEeIFupxIGV ciMk6t3pDrq7n7Vi/faqT+c4vnjazJi0UMfYnnAzYBa9+NkfW0w5W9Uy7kW/v7SffH/2yFiK 9HKkJqkN9xYEYaxtfl5pelF8idoxMZpTvCZY7jhnl2IemZCBMs6s338wS12Qro5WEAxV6cjD VSdmcD5l9plhKGLmgVNCTe8DPv81oDn9s0cIRLg9wNnDtj8aIiH8lBHwfUkpn32iv0uMV6Ae sLxhDWfOR4N+wu1gzXWgLel4drkCJcuYK5IL1qaZDcuGR8RPo3jbFO7Y Message-ID: <9519edb7-456a-a2fa-659e-3e5a1ff89466@suse.cz> Date: Tue, 12 Nov 2019 08:17:57 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: <1515636190-24061-10-git-send-email-keescook@chromium.org> Content-Type: text/plain; charset=iso-8859-2 Content-Language: en-US Content-Transfer-Encoding: 7bit On 11. 01. 18, 3:02, Kees Cook wrote: > From: David Windsor > > Mark the kmalloc slab caches as entirely whitelisted. These caches > are frequently used to fulfill kernel allocations that contain data > to be copied to/from userspace. Internal-only uses are also common, > but are scattered in the kernel. For now, mark all the kmalloc caches > as whitelisted. > > This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY > whitelisting code in the last public patch of grsecurity/PaX based on my > understanding of the code. Changes or omissions from the original code are > mine and don't reflect the original grsecurity/PaX code. > > Signed-off-by: David Windsor > [kees: merged in moved kmalloc hunks, adjust commit log] > Cc: Pekka Enberg > Cc: David Rientjes > Cc: Joonsoo Kim > Cc: Andrew Morton > Cc: linux-mm@kvack.org > Cc: linux-xfs@vger.kernel.org > Signed-off-by: Kees Cook > Acked-by: Christoph Lameter > --- > mm/slab.c | 3 ++- > mm/slab.h | 3 ++- > mm/slab_common.c | 10 ++++++---- > 3 files changed, 10 insertions(+), 6 deletions(-) > > diff --git a/mm/slab.c b/mm/slab.c > index b9b0df620bb9..dd367fe17a4e 100644 > --- a/mm/slab.c > +++ b/mm/slab.c ... > @@ -1098,7 +1099,8 @@ void __init setup_kmalloc_cache_index_table(void) > static void __init new_kmalloc_cache(int idx, slab_flags_t flags) > { > kmalloc_caches[idx] = create_kmalloc_cache(kmalloc_info[idx].name, > - kmalloc_info[idx].size, flags); > + kmalloc_info[idx].size, flags, 0, > + kmalloc_info[idx].size); > } > > /* > @@ -1139,7 +1141,7 @@ void __init create_kmalloc_caches(slab_flags_t flags) > > BUG_ON(!n); > kmalloc_dma_caches[i] = create_kmalloc_cache(n, > - size, SLAB_CACHE_DMA | flags); > + size, SLAB_CACHE_DMA | flags, 0, 0); Hi, was there any (undocumented) reason NOT to mark DMA caches as usercopy? We are seeing this on s390x: > usercopy: Kernel memory overwrite attempt detected to SLUB object 'dma-kmalloc-1k' (offset 0, size 11)! > ------------[ cut here ]------------ > kernel BUG at mm/usercopy.c:99! See: https://bugzilla.suse.com/show_bug.cgi?id=1156053 This indeed fixes it: --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -1290,7 +1290,8 @@ void __init create_kmalloc_caches(slab_flags_t flags) kmalloc_caches[KMALLOC_DMA][i] = create_kmalloc_cache( kmalloc_info[i].name[KMALLOC_DMA], kmalloc_info[i].size, - SLAB_CACHE_DMA | flags, 0, 0); + SLAB_CACHE_DMA | flags, 0, + kmalloc_info[i].size); } } #endif thanks, -- js suse labs