From patchwork Thu Jan 11 02:02:50 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 10156619 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 B432D605BA for ; Thu, 11 Jan 2018 02:13:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A1A542874B for ; Thu, 11 Jan 2018 02:13:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 95B822874E; Thu, 11 Jan 2018 02:13:51 +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 C2BCC2874B for ; Thu, 11 Jan 2018 02:13:49 +0000 (UTC) Received: (qmail 30114 invoked by uid 550); 11 Jan 2018 02:10:14 -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 29804 invoked from network); 11 Jan 2018 02:10:03 -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=cHB2F/Yz6P6r9aNJ3lpILjggOeGYjgFQ1X/Tj7q44/0=; b=Z9GHN/NTDw3tdsjUzdH0UVRgK/IFzYlcdxvu7pu35qz/6iBPnI4ZT2b0mUDS6poQlk eYleMcaoR9WMrvKsjMa2xlVrg0d8mI9NgjQcaen3mh4STimtqlXDU/bsXT59TcMGI0bZ ub7t7Zcr/9DjI/kmGWENOWoOmFQfeoQmIKYv8= 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=cHB2F/Yz6P6r9aNJ3lpILjggOeGYjgFQ1X/Tj7q44/0=; b=iIigKdX8U77tJsK4HE/GIIotPHik+HEgyIbH10Ql+5VNyRwJxsxHX98VRp1W3a/lhC DvQvCoRJZXL0dRpNuJKFWQBgC08hw/mlfIGW0ze2kkUke80Be2hlAc1XSJfGIsT3Fmq4 0XJbOA8pdhy4pyAbzM5IyP0e2w7JKkXObRDVN9QYeP7SCHmmRBhegOY6vOFeuY3yPoSr 2seSulBQnuVnF/V1yRQTUa4K0+DpdG5TfugmhIo4iJYC1FHOwYDDUpaAdiZxbsxiD8zM GXqD8TqHT46aCxzlUEeW6YlEikih1fLVYBoseMKikZ4DHGov+IsqkGho/W28MLNIzjYW Gyqw== X-Gm-Message-State: AKwxyteZIZouzAYIoKdfHUPY4UAHBndIlN4bDckXYgN981i5/YHVKaI6 2cdQc/o8lEXeHogcCh8NGhqxAA== X-Google-Smtp-Source: ACJfBosaFdHt51ey6dvtA/gEV5U1eZb6CGJMS16sLngz5B5ofRQNU5kiimr0V9WPwOzyInZLOoWf0g== X-Received: by 10.101.81.197 with SMTP id i5mr1298105pgq.220.1515636591391; Wed, 10 Jan 2018 18:09:51 -0800 (PST) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , David Windsor , Mike Marshall , Linus Torvalds , Alexander Viro , Andrew Morton , 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, linux-mm@kvack.org, kernel-hardening@lists.openwall.com Date: Wed, 10 Jan 2018 18:02:50 -0800 Message-Id: <1515636190-24061-19-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1515636190-24061-1-git-send-email-keescook@chromium.org> References: <1515636190-24061-1-git-send-email-keescook@chromium.org> Subject: [kernel-hardening] [PATCH 18/38] orangefs: Define usercopy region in orangefs_inode_cache slab cache X-Virus-Scanned: ClamAV using ClamSMTP From: David Windsor orangefs symlink pathnames, stored in struct orangefs_inode_s.link_target and therefore contained in the orangefs_inode_cache, need to be copied to/from userspace. cache object allocation: fs/orangefs/super.c: orangefs_alloc_inode(...): ... orangefs_inode = kmem_cache_alloc(orangefs_inode_cache, ...); ... return &orangefs_inode->vfs_inode; fs/orangefs/orangefs-utils.c: exofs_symlink(...): ... inode->i_link = orangefs_inode->link_target; example usage trace: readlink_copy+0x43/0x70 vfs_readlink+0x62/0x110 SyS_readlinkat+0x100/0x130 fs/namei.c: readlink_copy(..., link): ... copy_to_user(..., link, len); (inlined in vfs_readlink) generic_readlink(dentry, ...): struct inode *inode = d_inode(dentry); const char *link = inode->i_link; ... readlink_copy(..., link); In support of usercopy hardening, this patch defines a region in the orangefs_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 dynamically sized 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, provide usage trace] Cc: Mike Marshall Signed-off-by: Kees Cook --- fs/orangefs/super.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/orangefs/super.c b/fs/orangefs/super.c index 36f1390b5ed7..62d49e53061c 100644 --- a/fs/orangefs/super.c +++ b/fs/orangefs/super.c @@ -610,11 +610,16 @@ void orangefs_kill_sb(struct super_block *sb) int orangefs_inode_cache_initialize(void) { - orangefs_inode_cache = kmem_cache_create("orangefs_inode_cache", - sizeof(struct orangefs_inode_s), - 0, - ORANGEFS_CACHE_CREATE_FLAGS, - orangefs_inode_cache_ctor); + orangefs_inode_cache = kmem_cache_create_usercopy( + "orangefs_inode_cache", + sizeof(struct orangefs_inode_s), + 0, + ORANGEFS_CACHE_CREATE_FLAGS, + offsetof(struct orangefs_inode_s, + link_target), + sizeof_field(struct orangefs_inode_s, + link_target), + orangefs_inode_cache_ctor); if (!orangefs_inode_cache) { gossip_err("Cannot create orangefs_inode_cache\n");