From patchwork Mon Jun 19 23:36:22 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 9798041 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 2FC8B60381 for ; Mon, 19 Jun 2017 23:38:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2D50626C9B for ; Mon, 19 Jun 2017 23:38:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 221A127DCD; Mon, 19 Jun 2017 23:38:06 +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=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID 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 10B7B26C9B for ; Mon, 19 Jun 2017 23:38:04 +0000 (UTC) Received: (qmail 13954 invoked by uid 550); 19 Jun 2017 23:37:19 -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 11604 invoked from network); 19 Jun 2017 23:37:02 -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=XP8bQZn+fgzd9e7v1WKgu51ppbdy7zJnAuoRHFdE1Tk=; b=Sd1BSJhltqE1SJYWLWsmzZOLntREnA7LYHwTYSw8GWjNKsKPzGqVzapYJ7Imi1OOwv 3GMSz6kwm4m5NAycrjta88DNXqpB068AD5e+ClXyGQlTxnjJwVR7ITn5L49elXchU6zC W964LQF8TZ8x4VeMngqhaN/uFsDWKpAd96SbU= 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=XP8bQZn+fgzd9e7v1WKgu51ppbdy7zJnAuoRHFdE1Tk=; b=hKR2+0Ld1VGuj02zcE6rrDncztlUlVR42eOVUt8DRte+sm7Uxwsamx37jidGi2wXak TLGt0gf3bzj6z4VoohJGS/Xhu+v8Wdk4ot8lU7PJE3TiEYw0b3J8jWZeVkM61dzcfvWe cgfaxOkfY+GL1amzeCO0RZkhcgz4kZUf2GGw40bqsqTPp2scz3egSFfxrBRmZVMWfv1W VyMI7LbKEMziPOKwQF3NGX6Sfmat8Kh5FY0QxQWtBnJhNptpdIZ1Smo3HCiV/eE9gMot H+MPxwheElas/o/I4cpf8M6FmYtSrByCDUnc6XG6+hY4cJwnGKQU5A3LbNIXyn1NmboR rgMw== X-Gm-Message-State: AKS2vOz8M3frUBXlz7oNxipf/pM5PMERRHlERjDh1BEpdEN+o6LWfrFn Z1cmeuy8P07P4pfb X-Received: by 10.98.137.217 with SMTP id n86mr26881689pfk.85.1497915410740; Mon, 19 Jun 2017 16:36:50 -0700 (PDT) From: Kees Cook To: kernel-hardening@lists.openwall.com Cc: Kees Cook , David Windsor , linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Mon, 19 Jun 2017 16:36:22 -0700 Message-Id: <1497915397-93805-9-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1497915397-93805-1-git-send-email-keescook@chromium.org> References: <1497915397-93805-1-git-send-email-keescook@chromium.org> Subject: [kernel-hardening] [PATCH 08/23] ext2: define usercopy region in ext2_inode_cache slab cache X-Virus-Scanned: ClamAV using ClamSMTP From: David Windsor The ext2 symlink pathnames, stored in struct ext2_inode_info.i_data and therefore contained in the ext2_inode_cache slab cache, need to be copied to/from userspace. In support of usercopy hardening, this patch defines a region in the ext2_inode_cache slab cache in which userspace copy operations are allowed. This region is known as the slab cache's usercopy region. Slab caches can now check that each copy operation involving cache-managed memory falls entirely within the slab's usercopy region. 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: adjust commit log] Signed-off-by: Kees Cook --- fs/ext2/super.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 9c2028b50e5c..3e2aa21bc616 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -219,11 +219,13 @@ static void init_once(void *foo) static int __init init_inodecache(void) { - ext2_inode_cachep = kmem_cache_create("ext2_inode_cache", - sizeof(struct ext2_inode_info), - 0, (SLAB_RECLAIM_ACCOUNT| - SLAB_MEM_SPREAD|SLAB_ACCOUNT), - init_once); + ext2_inode_cachep = kmem_cache_create_usercopy("ext2_inode_cache", + sizeof(struct ext2_inode_info), 0, + (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| + SLAB_ACCOUNT), + offsetof(struct ext2_inode_info, i_data), + sizeof_field(struct ext2_inode_info, i_data), + init_once); if (ext2_inode_cachep == NULL) return -ENOMEM; return 0;