From patchwork Tue Jun 18 23:05:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 11003057 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9B21C112C for ; Tue, 18 Jun 2019 23:07:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8D1CE28B00 for ; Tue, 18 Jun 2019 23:07:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 81C5028B2C; Tue, 18 Jun 2019 23:07:08 +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=-7.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D89B328B00 for ; Tue, 18 Jun 2019 23:07:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730933AbfFRXHH (ORCPT ); Tue, 18 Jun 2019 19:07:07 -0400 Received: from sonic309-22.consmr.mail.bf2.yahoo.com ([74.6.129.196]:43538 "EHLO sonic309-22.consmr.mail.bf2.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730966AbfFRXHH (ORCPT ); Tue, 18 Jun 2019 19:07:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1560899225; bh=Ynd1NBD2PKeWyHg2goEWhFP1IQ7fVdL/bsSh5nybmrc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=OdHtQPpDEGW07B/yrkN6AEX1LSpgj2vj30JS/8cCasWVj6dde6gWRZmy5/3Cc9RRKUl3yTQQS/klnmyI/s2ivMCbMzHmkcEUKuoSA1uWhO6BKqhaZ96esQ9UYjWcwj97z7rGFoOpr6/P9PQQJOqjFRLa00XGaqp4M7XTm1UAOl2WPFsvs2rviW1mD+NHTAQCi0XoFYx8n1Z2i0pfHEse46iknAk/kKztdUHvoKPP+nq8tbqozcS7yMYX0MnZJ28guYR/tm9d18C94DQOUA/GNncyfqc5VXWWsmkmhTU9ZNE2FtRMw2oWNi8g5ZrUPZer1ZIZOMGmIU2VUGMwETSqag== X-YMail-OSG: Sdr3ndAVM1nRVunZNsCmpIgLx_vqg1pt6RbuY9tp9zuMs5v90w3KI.kQiWwag3q A35HEFUvY6J1IW.B7hPwBUHdAXcnDdF0NjyImTn_GZey37tRFH2RsOlvHMteBJ7.sYujQGwyj0J4 gtI2lrsnAu70AB9mJ_UPSXRV7_O4ob6ghiAmkPqN5rXXyVfV_.RbPwCUqFBaCBvTfc5rYDy3fAso Y7mSr0b8hzPQi_pS7bjWbpD6rVRxK.y7wQDE4EEGb0ptDOkAUiIDHhWATU_hN.7uWWQvGoymTrZB lNaC2T1eruwUaQw1hVcwSYDwQwwdPHx2wCjFzgWiVnemB8PXGEUesTc29bXPHGPooNOgwobc.FRO zbjyXpPZK7gXhpV5.nCuOKxsNb9NQ96VJ_5nSiXjJMLun3Y5EyTPjLYT1TJCKermjNw_vjGpC7jf IhZkssjnJxQkRONpKx6J.rqDbNywg.id5COV.sYIs_mai.T4kr9vGutrkW1HHZnSRB9MDyw6bumq SY3hZzKqSxDRITtg7gGdQthtwrzE0b67FUW7TIoU0DsDzuEnOfE2T2WN1QvNTS6BE9f3VLg4f57N d.1IyqkqnSUSiH8ki5zQUavGAw9TuGHh8edxiDX0LcbBrQcsg71te6Q_DkkQbeVHRBGU6nT25d.b 3.BB.B0.cMZXDsMmRqom34SgUB52wJpFvXmBLXOE8rZJvx1bwrKpmBc40srm0FLJSR6KtbNXcjUD H40vl4vCIlSKbA4R1i5db5Yk8J4or_3V0U4e9GiOu2xCYZQBiE4y0h_vWqmaQYx_w34SbwvkHo09 lecJ6.GyL.NnumQFqBygNTUJy8hMrMu.JjncuFJi0PVRjy4Z2k1WtrlrhPcHT03Wax0B6mSAi1kd Q9CZP5woMwMNCgRckGP9LeDY0jjhyvB5Y1ZbJqENYxMaAkssEfJ6z.ODb_sAwmTFZwjUFDMNqTqQ t7d6Xo9epj8eaC7CUw0dChKT73x86EWxiT5uuZ8O6tfTMkRkR4Cs.s2MvVIJV2jZf429NR9RrWi4 pK4Qk.m5Yy9mkWGIPB5_0RwEGL.kkV0CajrHagh5oHuCJHDse.ZEs1fDjzRYGGhiSh6QKM9JEn_s Y4Ce69dZHDgEYIJg7RujpERWNLNDmIZf2z56fJPM3_NRGwlu7Bq7jCsgHoX8iuR6wuREp4Ki7GPr VrCsp0pNU4AbEmpVyDePwC08RHunRNED7.oH7TYaNS.niY9wgb7hsLKNWhQmq2075SIyO1X4pINc 8zTAYFmfVCgLb6MPaBJJgpNLx_13hL3k8IPH2jgKf1qxmStqIx04- Received: from sonic.gate.mail.ne1.yahoo.com by sonic309.consmr.mail.bf2.yahoo.com with HTTP; Tue, 18 Jun 2019 23:07:05 +0000 Received: from c-73-223-4-185.hsd1.ca.comcast.net (EHLO localhost.net) ([73.223.4.185]) by smtp416.mail.bf1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID 9bd52d88915a86244e569f3c22bd3931; Tue, 18 Jun 2019 23:07:01 +0000 (UTC) From: Casey Schaufler To: casey.schaufler@intel.com, jmorris@namei.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Cc: casey@schaufler-ca.com, keescook@chromium.org, john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp, paul@paul-moore.com, sds@tycho.nsa.gov Subject: [PATCH v2 19/25] LSM: Use lsmcontext in security_inode_getsecctx Date: Tue, 18 Jun 2019 16:05:45 -0700 Message-Id: <20190618230551.7475-20-casey@schaufler-ca.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190618230551.7475-1-casey@schaufler-ca.com> References: <20190618230551.7475-1-casey@schaufler-ca.com> MIME-Version: 1.0 Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Change the security_inode_getsecctx() interface to fill a lsmcontext structure instead of data and length pointers. This provides the information about which LSM created the context so that security_release_secctx() can use the correct hook. A lsmcontext is used within kernfs to store the security information as well. Signed-off-by: Casey Schaufler --- fs/kernfs/dir.c | 8 ++------ fs/kernfs/inode.c | 34 ++++++++++++---------------------- fs/kernfs/kernfs-internal.h | 3 +-- fs/nfsd/nfs4xdr.c | 23 +++++++++-------------- include/linux/security.h | 5 +++-- security/security.c | 13 +++++++++++-- 6 files changed, 38 insertions(+), 48 deletions(-) diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 92afad387237..1d000289d8b7 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -532,12 +532,8 @@ void kernfs_put(struct kernfs_node *kn) kfree_const(kn->name); if (kn->iattr) { - struct lsmcontext scaff; /* scaffolding */ - if (kn->iattr->ia_secdata) { - lsmcontext_init(&scaff, kn->iattr->ia_secdata, - kn->iattr->ia_secdata_len, 0); - security_release_secctx(&scaff); - } + if (kn->iattr->ia_context.context) + security_release_secctx(&kn->iattr->ia_context); simple_xattrs_free(&kn->iattr->xattrs); kmem_cache_free(kernfs_iattrs_cache, kn->iattr); } diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c index 02cde9dac5ee..ffbf7863306d 100644 --- a/fs/kernfs/inode.c +++ b/fs/kernfs/inode.c @@ -135,21 +135,14 @@ int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr) return error; } -static int kernfs_node_setsecdata(struct kernfs_iattrs *attrs, void **secdata, - u32 *secdata_len) +static void kernfs_node_setsecdata(struct kernfs_iattrs *attrs, + struct lsmcontext *cp) { - void *old_secdata; - size_t old_secdata_len; + struct lsmcontext old_context; - old_secdata = attrs->ia_secdata; - old_secdata_len = attrs->ia_secdata_len; - - attrs->ia_secdata = *secdata; - attrs->ia_secdata_len = *secdata_len; - - *secdata = old_secdata; - *secdata_len = old_secdata_len; - return 0; + old_context = attrs->ia_context; + attrs->ia_context = *cp; + *cp = old_context; } ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size) @@ -192,8 +185,8 @@ static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode) * persistent copy in kernfs_node. */ set_inode_attr(inode, &attrs->ia_iattr); - security_inode_notifysecctx(inode, attrs->ia_secdata, - attrs->ia_secdata_len); + security_inode_notifysecctx(inode, attrs->ia_context.context, + attrs->ia_context.len); } if (kernfs_type(kn) == KERNFS_DIR) @@ -350,8 +343,6 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler, struct kernfs_node *kn = inode->i_private; struct kernfs_iattrs *attrs; struct lsmcontext context; - void *secdata; - u32 secdata_len = 0; int error; attrs = kernfs_iattrs(kn); @@ -361,18 +352,17 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler, error = security_inode_setsecurity(inode, suffix, value, size, flags); if (error) return error; - error = security_inode_getsecctx(inode, &secdata, &secdata_len); + error = security_inode_getsecctx(inode, &context); if (error) return error; mutex_lock(&kernfs_mutex); - error = kernfs_node_setsecdata(attrs, &secdata, &secdata_len); + kernfs_node_setsecdata(attrs, &context); mutex_unlock(&kernfs_mutex); - if (secdata) { - lsmcontext_init(&context, secdata, secdata_len, 0); + if (context.context) security_release_secctx(&context); - } + return error; } diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h index 0b7d197a904c..844a028d282f 100644 --- a/fs/kernfs/kernfs-internal.h +++ b/fs/kernfs/kernfs-internal.h @@ -21,8 +21,7 @@ struct kernfs_iattrs { struct iattr ia_iattr; - void *ia_secdata; - u32 ia_secdata_len; + struct lsmcontext ia_context; struct simple_xattrs xattrs; }; diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index bb3db033e144..1209083565dd 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2304,11 +2304,11 @@ nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types) #ifdef CONFIG_NFSD_V4_SECURITY_LABEL static inline __be32 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp, - void *context, int len) + struct lsmcontext *context) { __be32 *p; - p = xdr_reserve_space(xdr, len + 4 + 4 + 4); + p = xdr_reserve_space(xdr, context->len + 4 + 4 + 4); if (!p) return nfserr_resource; @@ -2318,13 +2318,13 @@ nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp, */ *p++ = cpu_to_be32(0); /* lfs */ *p++ = cpu_to_be32(0); /* pi */ - p = xdr_encode_opaque(p, context, len); + p = xdr_encode_opaque(p, context->context, context->len); return 0; } #else static inline __be32 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp, - void *context, int len) + struct lsmcontext *context) { return 0; } #endif @@ -2420,9 +2420,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, __be32 status; int err; struct nfs4_acl *acl = NULL; - struct lsmcontext scaff; /* scaffolding */ - void *context = NULL; - int contextlen; + struct lsmcontext context; bool contextsupport = false; struct nfsd4_compoundres *resp = rqstp->rq_resp; u32 minorversion = resp->cstate.minorversion; @@ -2479,7 +2477,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) { if (exp->ex_flags & NFSEXP_SECURITY_LABEL) err = security_inode_getsecctx(d_inode(dentry), - &context, &contextlen); + &context); else err = -EOPNOTSUPP; contextsupport = (err == 0); @@ -2908,8 +2906,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, } if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) { - status = nfsd4_encode_security_label(xdr, rqstp, context, - contextlen); + status = nfsd4_encode_security_label(xdr, rqstp, &context); if (status) goto out; } @@ -2920,10 +2917,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, out: #ifdef CONFIG_NFSD_V4_SECURITY_LABEL - if (context) { - lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/ - security_release_secctx(&scaff); - } + if (context.context) + security_release_secctx(&context); #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */ kfree(acl); if (tempfh) { diff --git a/include/linux/security.h b/include/linux/security.h index 92c4960dd57f..9f26ea11d307 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -483,7 +483,7 @@ void security_release_secctx(struct lsmcontext *cp); void security_inode_invalidate_secctx(struct inode *inode); int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen); int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen); -int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen); +int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp); #else /* CONFIG_SECURITY */ static inline int call_lsm_notifier(enum lsm_event event, void *data) @@ -1284,7 +1284,8 @@ static inline int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 { return -EOPNOTSUPP; } -static inline int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) +static inline int security_inode_getsecctx(struct inode *inode, + struct lsmcontext *cp) { return -EOPNOTSUPP; } diff --git a/security/security.c b/security/security.c index 23d8049ec0c1..7b8427560646 100644 --- a/security/security.c +++ b/security/security.c @@ -2131,9 +2131,18 @@ int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) } EXPORT_SYMBOL(security_inode_setsecctx); -int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) +int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp) { - return call_int_hook(inode_getsecctx, -EOPNOTSUPP, inode, ctx, ctxlen); + int *display = current->security; + struct security_hook_list *hp; + + hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) + if (*display == 0 || *display == hp->slot) { + cp->slot = hp->slot; + return hp->hook.inode_getsecctx(inode, + (void **)&cp->context, &cp->len); + } + return -EOPNOTSUPP; } EXPORT_SYMBOL(security_inode_getsecctx);