From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 924D3C04AB6 for ; Tue, 28 May 2019 15:12:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 728FF206C1 for ; Tue, 28 May 2019 15:12:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727801AbfE1PM5 (ORCPT ); Tue, 28 May 2019 11:12:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55666 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726826AbfE1PMz (ORCPT ); Tue, 28 May 2019 11:12:55 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4EC423083394; Tue, 28 May 2019 15:12:55 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-125-65.rdu2.redhat.com [10.10.125.65]) by smtp.corp.redhat.com (Postfix) with ESMTP id C1179AFE55; Tue, 28 May 2019 15:12:53 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 13/25] fsinfo: Support SELinux superblock parameter retrieval [ver #13] From: David Howells To: viro@zeniv.linux.org.uk Cc: dhowells@redhat.com, raven@themaw.net, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, mszeredi@redhat.com Date: Tue, 28 May 2019 16:12:53 +0100 Message-ID: <155905637302.1662.8473297942541287404.stgit@warthog.procyon.org.uk> In-Reply-To: <155905626142.1662.18430571708534506785.stgit@warthog.procyon.org.uk> References: <155905626142.1662.18430571708534506785.stgit@warthog.procyon.org.uk> User-Agent: StGit/unknown-version MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.44]); Tue, 28 May 2019 15:12:55 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add support to SELinux for retrieval of the superblock parameters by fsinfo(FSINFO_ATTR_LSM_PARAMETERS). Signed-off-by: David Howells --- security/selinux/hooks.c | 41 +++++++++++++++++++++++++++++ security/selinux/include/security.h | 2 + security/selinux/ss/services.c | 49 +++++++++++++++++++++++++++++++++++ 3 files changed, 92 insertions(+) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index c61787b15f27..9b5dbdcde9e6 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -91,6 +91,7 @@ #include #include #include /* for hashlen_string() */ +#include #include #include "avc.h" @@ -2735,6 +2736,43 @@ static int selinux_sb_statfs(struct dentry *dentry) return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); } +#ifdef CONFIG_FSINFO +/* + * Retrieve the SELinux filesystem information, including mount parameters. + */ +static int selinux_sb_fsinfo(struct path *path, struct fsinfo_kparams *params) +{ + struct superblock_security_struct *sbsec = path->dentry->d_sb->s_security; + + switch (params->request) { + case FSINFO_ATTR_LSM_PARAMETERS: + if (!(sbsec->flags & SE_SBINITIALIZED) || + !selinux_state.initialized) + return params->usage; + + if (sbsec->flags & FSCONTEXT_MNT) + fsinfo_note_sid(params, FSCONTEXT_STR, sbsec->sid); + if (sbsec->flags & CONTEXT_MNT) + fsinfo_note_sid(params, CONTEXT_STR, sbsec->mntpoint_sid); + if (sbsec->flags & DEFCONTEXT_MNT) + fsinfo_note_sid(params, DEFCONTEXT_STR, sbsec->def_sid); + if (sbsec->flags & ROOTCONTEXT_MNT) { + struct dentry *root = sbsec->sb->s_root; + struct inode_security_struct *isec = backing_inode_security(root); + fsinfo_note_sid(params, ROOTCONTEXT_STR, isec->sid); + } + if (sbsec->flags & SBLABEL_MNT) + fsinfo_note_param(params, SECLABEL_STR, NULL); + + return params->usage; + + default: + return -ENODATA; + } + return 0; +} +#endif + static int selinux_mount(const char *dev_name, const struct path *path, const char *type, @@ -6761,6 +6799,9 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), +#ifdef CONFIG_FSINFO + LSM_HOOK_INIT(sb_fsinfo, selinux_sb_fsinfo), +#endif LSM_HOOK_INIT(sb_mount, selinux_mount), LSM_HOOK_INIT(sb_umount, selinux_umount), LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 111121281c47..e9617bfcc6ee 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -67,6 +67,7 @@ #define SECLABEL_STR "seclabel" struct netlbl_lsm_secattr; +struct fsinfo_kparams; extern int selinux_enabled; @@ -258,6 +259,7 @@ int security_sid_to_context_force(struct selinux_state *state, int security_sid_to_context_inval(struct selinux_state *state, u32 sid, char **scontext, u32 *scontext_len); +void fsinfo_note_sid(struct fsinfo_kparams *params, const char *key, u32 sid); int security_context_to_sid(struct selinux_state *state, const char *scontext, u32 scontext_len, diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index cc043bc8fd4c..1111b02a999b 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -50,6 +50,7 @@ #include #include #include +#include #include #include "flask.h" @@ -1374,6 +1375,54 @@ int security_sid_to_context_inval(struct selinux_state *state, u32 sid, scontext_len, 1, 1); } +#ifdef CONFIG_FSINFO +void fsinfo_note_sid(struct fsinfo_kparams *params, const char *key, u32 sid) +{ + struct selinux_state *state = &selinux_state; + struct policydb *policydb; + struct context *context; + const char *val = "<<>>"; + char *p; + int n; + + if (!state->initialized) { + if (sid <= SECINITSID_NUM) { + val = initial_sid_to_string[sid]; + goto out; + } + + pr_err("SELinux: %s: called before initial " + "load_policy on unknown SID %d\n", __func__, sid); + goto out; + } + + read_lock(&state->ss->policy_rwlock); + + policydb = &state->ss->policydb; + context = sidtab_search(state->ss->sidtab, sid); + if (!context) { + pr_err("SELinux: %s: unrecognized SID %d\n", __func__, sid); + } else { + /* Copy the user name, role name and type name into the scratch + * buffer and then tack on the MLS. + */ + val = p = params->scratch_buffer; + n = sprintf(p, "%s:%s:%s", + sym_name(policydb, SYM_USERS, context->user - 1), + sym_name(policydb, SYM_ROLES, context->role - 1), + sym_name(policydb, SYM_TYPES, context->type - 1)); + + p += n; + mls_sid_to_context(policydb, context, &p); + *p = 0; + } + + read_unlock(&state->ss->policy_rwlock); +out: + fsinfo_note_param(params, key, val); +} +#endif + /* * Caveat: Mutates scontext. */