From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752992AbdFSXid (ORCPT ); Mon, 19 Jun 2017 19:38:33 -0400 Received: from mail-pg0-f52.google.com ([74.125.83.52]:34756 "EHLO mail-pg0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752749AbdFSXg5 (ORCPT ); Mon, 19 Jun 2017 19:36:57 -0400 From: Kees Cook To: kernel-hardening@lists.openwall.com Cc: Kees Cook , David Windsor , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 10/23] vxfs: define usercopy region in vxfs_inode slab cache Date: Mon, 19 Jun 2017 16:36:24 -0700 Message-Id: <1497915397-93805-11-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> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Windsor The vxfs symlink pathnames, stored in struct vxfs_inode_info.vii_immed.vi_immed and therefore contained in the vxfs_inode slab cache, need to be copied to/from userspace. In support of usercopy hardening, this patch defines a region in the vxfs_inode 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/freevxfs/vxfs_super.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/freevxfs/vxfs_super.c b/fs/freevxfs/vxfs_super.c index 455ce5b77e9b..c143e18d5a65 100644 --- a/fs/freevxfs/vxfs_super.c +++ b/fs/freevxfs/vxfs_super.c @@ -332,9 +332,13 @@ vxfs_init(void) { int rv; - vxfs_inode_cachep = kmem_cache_create("vxfs_inode", + vxfs_inode_cachep = kmem_cache_create_usercopy("vxfs_inode", sizeof(struct vxfs_inode_info), 0, - SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL); + SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, + offsetof(struct vxfs_inode_info, vii_immed.vi_immed), + sizeof_field(struct vxfs_inode_info, + vii_immed.vi_immed), + NULL); if (!vxfs_inode_cachep) return -ENOMEM; rv = register_filesystem(&vxfs_fs_type); -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f69.google.com (mail-pg0-f69.google.com [74.125.83.69]) by kanga.kvack.org (Postfix) with ESMTP id 68B826B0317 for ; Mon, 19 Jun 2017 19:36:52 -0400 (EDT) Received: by mail-pg0-f69.google.com with SMTP id 33so101532338pgx.14 for ; Mon, 19 Jun 2017 16:36:52 -0700 (PDT) Received: from mail-pg0-x22c.google.com (mail-pg0-x22c.google.com. [2607:f8b0:400e:c05::22c]) by mx.google.com with ESMTPS id r123si9092716pfr.180.2017.06.19.16.36.51 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Jun 2017 16:36:51 -0700 (PDT) Received: by mail-pg0-x22c.google.com with SMTP id u62so35468607pgb.3 for ; Mon, 19 Jun 2017 16:36:51 -0700 (PDT) From: Kees Cook Subject: [PATCH 10/23] vxfs: define usercopy region in vxfs_inode slab cache Date: Mon, 19 Jun 2017 16:36:24 -0700 Message-Id: <1497915397-93805-11-git-send-email-keescook@chromium.org> In-Reply-To: <1497915397-93805-1-git-send-email-keescook@chromium.org> References: <1497915397-93805-1-git-send-email-keescook@chromium.org> Sender: owner-linux-mm@kvack.org List-ID: To: kernel-hardening@lists.openwall.com Cc: Kees Cook , David Windsor , linux-mm@kvack.org, linux-kernel@vger.kernel.org From: David Windsor The vxfs symlink pathnames, stored in struct vxfs_inode_info.vii_immed.vi_immed and therefore contained in the vxfs_inode slab cache, need to be copied to/from userspace. In support of usercopy hardening, this patch defines a region in the vxfs_inode 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/freevxfs/vxfs_super.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/freevxfs/vxfs_super.c b/fs/freevxfs/vxfs_super.c index 455ce5b77e9b..c143e18d5a65 100644 --- a/fs/freevxfs/vxfs_super.c +++ b/fs/freevxfs/vxfs_super.c @@ -332,9 +332,13 @@ vxfs_init(void) { int rv; - vxfs_inode_cachep = kmem_cache_create("vxfs_inode", + vxfs_inode_cachep = kmem_cache_create_usercopy("vxfs_inode", sizeof(struct vxfs_inode_info), 0, - SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL); + SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, + offsetof(struct vxfs_inode_info, vii_immed.vi_immed), + sizeof_field(struct vxfs_inode_info, + vii_immed.vi_immed), + NULL); if (!vxfs_inode_cachep) return -ENOMEM; rv = register_filesystem(&vxfs_fs_type); -- 2.7.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Date: Mon, 19 Jun 2017 16:36:24 -0700 Message-Id: <1497915397-93805-11-git-send-email-keescook@chromium.org> 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 10/23] vxfs: define usercopy region in vxfs_inode slab cache To: kernel-hardening@lists.openwall.com Cc: Kees Cook , David Windsor , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: From: David Windsor The vxfs symlink pathnames, stored in struct vxfs_inode_info.vii_immed.vi_immed and therefore contained in the vxfs_inode slab cache, need to be copied to/from userspace. In support of usercopy hardening, this patch defines a region in the vxfs_inode 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/freevxfs/vxfs_super.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/freevxfs/vxfs_super.c b/fs/freevxfs/vxfs_super.c index 455ce5b77e9b..c143e18d5a65 100644 --- a/fs/freevxfs/vxfs_super.c +++ b/fs/freevxfs/vxfs_super.c @@ -332,9 +332,13 @@ vxfs_init(void) { int rv; - vxfs_inode_cachep = kmem_cache_create("vxfs_inode", + vxfs_inode_cachep = kmem_cache_create_usercopy("vxfs_inode", sizeof(struct vxfs_inode_info), 0, - SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL); + SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, + offsetof(struct vxfs_inode_info, vii_immed.vi_immed), + sizeof_field(struct vxfs_inode_info, + vii_immed.vi_immed), + NULL); if (!vxfs_inode_cachep) return -ENOMEM; rv = register_filesystem(&vxfs_fs_type); -- 2.7.4