From patchwork Mon Aug 28 21:34:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 9926239 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0E86B60375 for ; Mon, 28 Aug 2017 21:36:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 01F81287CE for ; Mon, 28 Aug 2017 21:36:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EAC5A287D4; Mon, 28 Aug 2017 21:36:13 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID, URIBL_BLACK autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 82AD3287CE for ; Mon, 28 Aug 2017 21:36:12 +0000 (UTC) Received: (qmail 11985 invoked by uid 550); 28 Aug 2017 21:35:34 -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: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 11862 invoked from network); 28 Aug 2017 21:35:30 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=QbOiL8kXI2ClelsY64M9nxedFr/xyCqdWsmR6AQJ4OM=; b=MBr4dETkkGLO/jRLwVq/XIW//L5cE3bW2C4ACIpHm2rW/TqArqWypBmRUZHYpiBV/7 oCuEU6bllBtyaO0usXiC3BM7VNv6BYjAoC78PMduL25E8aPBZaf8ilqgMPfYheGuFHz1 2/GCcIlxNi9+sc9cJobdkSCMMEz8NiRLZBSRI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=QbOiL8kXI2ClelsY64M9nxedFr/xyCqdWsmR6AQJ4OM=; b=BwB7yZIXrZEl+eADxTEE3LVSL7R5WC5bX8UbMdaVgbi5AUTD++ykv6wsNqHJD/mYCJ XoIt2vbgyPBaga4irseGkedfKGQGYrIJ+1nHMNdY77F2uBMI1ZWketmfAT08euxVLwM3 FBKIYwRXBHGKCuXLwzVn10tXQ9XrB+7v3qi6q2q03ABg9czmgsWtioXhXoUqHdu+2MG9 gmj1wYBVPCWGwzmT4EA1knG/VP5fjyyoP3emM1urvgK2UyLBp4C2PVvBesnF4ot1b+vC gjD5PV7+nIW+I4UYy5NxZQTwCbMf5IRrpP9dBCtXXKNCS6XzoTUGSTjHjuCARmCjVSaj 14Og== X-Gm-Message-State: AHYfb5jvjRngIda74lqCJebPv5T7OLce3fU+rEV7fOfspstZqoz8SY9J ES0854/DmQ141NKc X-Received: by 10.98.102.145 with SMTP id s17mr1824320pfj.227.1503956119059; Mon, 28 Aug 2017 14:35:19 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , David Windsor , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , linux-mm@kvack.org, kernel-hardening@lists.openwall.com Date: Mon, 28 Aug 2017 14:34:44 -0700 Message-Id: <1503956111-36652-4-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1503956111-36652-1-git-send-email-keescook@chromium.org> References: <1503956111-36652-1-git-send-email-keescook@chromium.org> Subject: [kernel-hardening] [PATCH v2 03/30] usercopy: Mark kmalloc caches as usercopy caches X-Virus-Scanned: ClamAV using ClamSMTP 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: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrew Morton Cc: linux-mm@kvack.org Signed-off-by: Kees Cook --- 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 df268999cf02..9af16f675927 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1291,7 +1291,8 @@ void __init kmem_cache_init(void) */ kmalloc_caches[INDEX_NODE] = create_kmalloc_cache( kmalloc_info[INDEX_NODE].name, - kmalloc_size(INDEX_NODE), ARCH_KMALLOC_FLAGS); + kmalloc_size(INDEX_NODE), ARCH_KMALLOC_FLAGS, + 0, kmalloc_size(INDEX_NODE)); slab_state = PARTIAL_NODE; setup_kmalloc_cache_index_table(); diff --git a/mm/slab.h b/mm/slab.h index 5d4b0fb6b7de..ec7d64debebd 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -96,7 +96,8 @@ struct kmem_cache *kmalloc_slab(size_t, gfp_t); extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags); extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size, - unsigned long flags); + unsigned long flags, size_t useroffset, + size_t usersize); extern void create_boot_cache(struct kmem_cache *, const char *name, size_t size, unsigned long flags, size_t useroffset, size_t usersize); diff --git a/mm/slab_common.c b/mm/slab_common.c index 4b1bca7c1a42..f662f4e2fa29 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -916,14 +916,15 @@ void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t siz } struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size, - unsigned long flags) + unsigned long flags, size_t useroffset, + size_t usersize) { struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); if (!s) panic("Out of memory when creating slab %s\n", name); - create_boot_cache(s, name, size, flags, 0, size); + create_boot_cache(s, name, size, flags, useroffset, usersize); list_add(&s->list, &slab_caches); memcg_link_cache(s); s->refcount = 1; @@ -1077,7 +1078,8 @@ void __init setup_kmalloc_cache_index_table(void) static void __init new_kmalloc_cache(int idx, unsigned long 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); } /* @@ -1118,7 +1120,7 @@ void __init create_kmalloc_caches(unsigned long flags) BUG_ON(!n); kmalloc_dma_caches[i] = create_kmalloc_cache(n, - size, SLAB_CACHE_DMA | flags); + size, SLAB_CACHE_DMA | flags, 0, 0); } } #endif