From mboxrd@z Thu Jan 1 00:00:00 1970 From: Seth Forshee Subject: [PATCH v3 12/21] fs: Refuse uid/gid changes which don't map into s_user_ns Date: Fri, 22 Apr 2016 10:38:29 -0500 Message-ID: <1461339521-123191-13-git-send-email-seth.forshee@canonical.com> References: <1461339521-123191-1-git-send-email-seth.forshee@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1461339521-123191-1-git-send-email-seth.forshee-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: fuse-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: "Eric W. Biederman" , Alexander Viro Cc: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Serge Hallyn , Seth Forshee , dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Miklos Szeredi , linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-raid-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, fuse-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Austin S Hemmelgarn , linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, selinux-+05T5uksL2qpZYMLLGbcSA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Pavel Tikhomirov List-Id: linux-bcache@vger.kernel.org Add checks to inode_change_ok to verify that uid and gid changes will map into the superblock's user namespace. If they do not fail with -EOVERFLOW. This cannot be overriden with ATTR_FORCE. Signed-off-by: Seth Forshee Acked-by: Serge Hallyn --- fs/attr.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/fs/attr.c b/fs/attr.c index 25b24d0f6c88..3cfaaac4a18e 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -42,6 +42,17 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr) return error; } + /* + * Verify that uid/gid changes are valid in the target namespace + * of the superblock. This cannot be overriden using ATTR_FORCE. + */ + if (ia_valid & ATTR_UID && + from_kuid(inode->i_sb->s_user_ns, attr->ia_uid) == (uid_t)-1) + return -EOVERFLOW; + if (ia_valid & ATTR_GID && + from_kgid(inode->i_sb->s_user_ns, attr->ia_gid) == (gid_t)-1) + return -EOVERFLOW; + /* If force is set do it anyway. */ if (ia_valid & ATTR_FORCE) return 0; -- 1.9.1 ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z -- fuse-devel mailing list To unsubscribe or subscribe, visit https://lists.sourceforge.net/lists/listinfo/fuse-devel