From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58836 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752979AbeDJJIw (ORCPT ); Tue, 10 Apr 2018 05:08:52 -0400 Subject: Patch "selinux: do not check open permission on sockets" has been added to the 4.4-stable tree To: sds@tycho.nsa.gov, alexander.levin@microsoft.com, gregkh@linuxfoundation.org, paul@paul-moore.com Cc: , From: Date: Tue, 10 Apr 2018 11:06:16 +0200 Message-ID: <152335117690119@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled selinux: do not check open permission on sockets to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: selinux-do-not-check-open-permission-on-sockets.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Tue Apr 10 10:31:53 CEST 2018 From: Stephen Smalley Date: Fri, 12 May 2017 12:41:24 -0400 Subject: selinux: do not check open permission on sockets From: Stephen Smalley [ Upstream commit ccb544781d34afdb73a9a73ae53035d824d193bf ] open permission is currently only defined for files in the kernel (COMMON_FILE_PERMS rather than COMMON_FILE_SOCK_PERMS). Construction of an artificial test case that tries to open a socket via /proc/pid/fd will generate a recvfrom avc denial because recvfrom and open happen to map to the same permission bit in socket vs file classes. open of a socket via /proc/pid/fd is not supported by the kernel regardless and will ultimately return ENXIO. But we hit the permission check first and can thus produce these odd/misleading denials. Omit the open check when operating on a socket. Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- security/selinux/hooks.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1942,8 +1942,9 @@ static inline u32 file_to_av(struct file static inline u32 open_file_to_av(struct file *file) { u32 av = file_to_av(file); + struct inode *inode = file_inode(file); - if (selinux_policycap_openperm) + if (selinux_policycap_openperm && inode->i_sb->s_magic != SOCKFS_MAGIC) av |= FILE__OPEN; return av; @@ -2912,6 +2913,7 @@ static int selinux_inode_permission(stru static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) { const struct cred *cred = current_cred(); + struct inode *inode = d_backing_inode(dentry); unsigned int ia_valid = iattr->ia_valid; __u32 av = FILE__WRITE; @@ -2927,8 +2929,10 @@ static int selinux_inode_setattr(struct ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) return dentry_has_perm(cred, dentry, FILE__SETATTR); - if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE) - && !(ia_valid & ATTR_FILE)) + if (selinux_policycap_openperm && + inode->i_sb->s_magic != SOCKFS_MAGIC && + (ia_valid & ATTR_SIZE) && + !(ia_valid & ATTR_FILE)) av |= FILE__OPEN; return dentry_has_perm(cred, dentry, av); Patches currently in stable-queue which might be from sds@tycho.nsa.gov are queue-4.4/selinux-do-not-check-open-permission-on-sockets.patch