From patchwork Tue Apr 7 00:01:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Casey Schaufler X-Patchwork-Id: 11477025 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 37D6F159A for ; Tue, 7 Apr 2020 00:19:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C55D2072A for ; Tue, 7 Apr 2020 00:19:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=yahoo.com header.i=@yahoo.com header.b="aTp6OLbz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726393AbgDGATk (ORCPT ); Mon, 6 Apr 2020 20:19:40 -0400 Received: from sonic311-31.consmr.mail.ne1.yahoo.com ([66.163.188.212]:36854 "EHLO sonic311-31.consmr.mail.ne1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726310AbgDGATk (ORCPT ); Mon, 6 Apr 2020 20:19:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1586218779; bh=iiZ85/apW67LStJFonXfNw/3jjgbvi5ga5uAoEmvE38=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From:Subject; b=aTp6OLbznq5iwBOA4EAbyBjR5k3YuvNR+6LqsIjyTMiRp45CTQAk44cGMf2oSh26NrxgYRzUW5nTmdK+2m7RS4HeIhh/YhGG0uMEFaxBpSi9k1xwxXTyFL0A3rmXhpjIA52rO8sUuHIzW7a4c7DUUTT8hoyl0yJrjOBYGTAbjrq16PjInsqikDGtm7Hn7t2kPrIFFjsMQlpexaH54r92Ol5BMTtM7s6bb39bY+wnmNLzJ8eqOIomB5rnwCmXnv8AHrnR0iFR1BcQQRTi8zYKoepaPzhRhXY9S4Xx8TkGJ/JCoxPd+0FYnKZLLn+6XFGGiZd1bQbWf/FJPduNNFIAZQ== X-YMail-OSG: oMN_LdgVM1nyxwDnpz46eUws47Kb7qmHGsjwvH76RAANMXKlogWEDIQQ53s0OTx paSgeAMJFfOEVYpFqSk8524BpTkEpJCZMPspNk3gUovaFaqT_HsklUTfWX_6toETCHMzy2GOKQ.3 WwllnI26U9VkN1qjcdGBb8rJCwrrCf7E1bD2m8W105xhWgv7y0NsfZlHUk9SE4bcn8W9UU.Bf8zc t2LC0GmCZDp0MQBwfOxbTWhMkJRPNfOg7lakQrMjyGMqe6Ot_Lotgg7sGGOAMcpmbHjMX8yZrfcn qKiuGrBh1uckCN8fHGL8sfBqMO_xWg.VlnYFZDD6Db1Ouma15Voag6G3o3aGz67thjLDh9q7l80w OE_cvvPtrncGATp2OcRLuzDyt29pbhGPusjH15aecoKlOCfMzZNXA_6b0Esz_fpEANHQUSMKcWWP ..S4961L6Q2dSwBqgn783FnKZO1NfoS3mH.XYetLZl6XzL5CYFohz6eer6z5b_mLmyiPWpL_fxHq jaBUeBKDQ3swhu7Fzpjgwe7o517bXuThkHv3ZbV7AbCm.z.e70f12V9FxY2qcuc3DIwVHqPqg6XJ tZFVFW._1.s55Pnca6gv3T903IW.5UdZHUJrvs16yWwknq8JktwHCUcUjtdYyt7U3qpKIvgeD7T1 1S2I63nyjC6Ubd5SYThTl8ZLqTTqaUzS_h7J6uQhh.NdiUn1BSmONrjLkFy1.JuY31uWqaFLSkKz zyYkHo8UhqKmQRRRGrc7qc61LQpzX8CLXZdMWbgd3Ky23xFs4KEhdq8EkazH891BCr.kJF.O35rm .VMeCBHCYnQ.TTVa4pHuEcdPaJyIWwWP90hHvJZDVR.aMkgLsXSTruiKOE.F7QGmpDmUWR4Lf2Z. tRftnE6VvI90nrJbthpURiQhgRmjW7N8ddHfpnSohV.6qeN_S7gY8hUbuDRCgUrDvAkvkzFc0lxW 1ZvS1YzfUhKvkxsO3xYonaBboV2Yrgm2RByl18kLO.NdCXogaOV8RcVnyV7NtbCo.xeWp609CSO_ DYmJ_A9ddvXxr617F0FCOUHlU7vgtRQdwwWWSngsGU5OLOHjjrg6IXatST4YOcdKlcPBI1DPtHy3 jsKyB3upFljmRUmJfK52TbdOsJRQq37.Vxi1TiT.ZgxPbBKHgyWryuO6FZE.rm_ZW2794KlcvcNV VveRqAmquiq6FFPdirFWTBJrHlnb3ukod2a71XkZa.50YuU9d5fDCUJT7iKJRLsQVa9dFWaYZipi k2DPJJ1w.inggaQwkSeENXoaa5w6pPooqJVd7L_SG4uwpI6QQY0mmcn4CcWmw9_2gxFnZlXPj6dL RZhWAsiDUHBE94eYdXLFjTP.LHkYwGK6IGs82YuT6GuD1cqrfqNihnfRjrhOM_46utFWc3zCJyfL rPsKLrqccbxdDaAuFqbeFQ8qaJB2XlTlJf0H7_.zlynyBp2qF0OqiFw-- Received: from sonic.gate.mail.ne1.yahoo.com by sonic311.consmr.mail.ne1.yahoo.com with HTTP; Tue, 7 Apr 2020 00:19:39 +0000 Received: by smtp407.mail.gq1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID ea1af58f83a714a42a96c4b340cba5cc; Tue, 07 Apr 2020 00:19:35 +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, linux-audit@redhat.com Subject: [PATCH v16 16/23] LSM: Use lsmcontext in security_inode_getsecctx Date: Mon, 6 Apr 2020 17:01:52 -0700 Message-Id: <20200407000159.43602-17-casey@schaufler-ca.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200407000159.43602-1-casey@schaufler-ca.com> References: <20200407000159.43602-1-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 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. Acked-by: Stephen Smalley Signed-off-by: Casey Schaufler Reviewed-by: Kees Cook --- fs/nfsd/nfs4xdr.c | 23 +++++++++-------------- include/linux/security.h | 5 +++-- security/security.c | 13 +++++++++++-- 3 files changed, 23 insertions(+), 18 deletions(-) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index df308b1b37fa..ac8eb77d0053 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2379,11 +2379,11 @@ 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; @@ -2393,13 +2393,13 @@ 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 @@ -2496,9 +2496,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, int err; struct nfs4_acl *acl = NULL; #ifdef CONFIG_NFSD_V4_SECURITY_LABEL - struct lsmcontext scaff; /* scaffolding */ - void *context = NULL; - int contextlen; + struct lsmcontext context = { }; #endif bool contextsupport = false; struct nfsd4_compoundres *resp = rqstp->rq_resp; @@ -2556,7 +2554,7 @@ 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); @@ -2986,8 +2984,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, #ifdef CONFIG_NFSD_V4_SECURITY_LABEL 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; } @@ -2999,10 +2996,8 @@ 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 ec64ccd2e168..fac5547dd89e 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -556,7 +556,7 @@ 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); int security_locked_down(enum lockdown_reason what); #else /* CONFIG_SECURITY */ @@ -1382,7 +1382,8 @@ 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 356c5cd94c48..84f33bd4990a 100644 --- a/security/security.c +++ b/security/security.c @@ -2211,9 +2211,18 @@ 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); + struct security_hook_list *hp; + + memset(cp, 0, sizeof(*cp)); + + hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) { + cp->slot = hp->lsmid->slot; + return hp->hook.inode_getsecctx(inode, (void **)&cp->context, + &cp->len); + } + return -EOPNOTSUPP; } EXPORT_SYMBOL(security_inode_getsecctx);