From patchwork Mon Jan 2 17:06:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 13086854 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 759B5C3DA7A for ; Mon, 2 Jan 2023 17:06:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236188AbjABRGI (ORCPT ); Mon, 2 Jan 2023 12:06:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53018 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236182AbjABRGH (ORCPT ); Mon, 2 Jan 2023 12:06:07 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFBBD64DE for ; Mon, 2 Jan 2023 09:06:06 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 91AABB80D0A for ; Mon, 2 Jan 2023 17:06:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B059C433D2 for ; Mon, 2 Jan 2023 17:06:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672679164; bh=deKo7xKBXd1+851snGqVAeCc1jQOGV7cZQKXoFMdifo=; h=Subject:From:To:Date:In-Reply-To:References:From; b=vJ0V8cEOI2zAqpkxYE6kiBMWfFMTr3IQarkdfJiRUpC3PS+/MoTNqzRrYokdNqdFq iItxAGRPiAltL10Bw7g7Pu0z9URlZO+qvp21fgyh3nCvCVwkn+OlUao+Nhwn5Q1m7U f9javRkzOuA713F0Izy5g0DkUtQx/pLrbCdDa2gYNVDRe3v8LMN0RnjliVr1kiarhA WA/ovtklbh9ZyBcf+Ea2nkc2vPIFA48iW8VomXlimK0Vjlsp7/FruG6L6DpbMkS4Vy /7NxI1QBIvRKdU+Smdn09cMc07ReBBvtobQzda3Oo5vYg4Q38aU5ATratxxLiI1SCY sMwKnUEeK0bWQ== Subject: [PATCH v1 06/25] SUNRPC: Convert svcauth_tls_accept() to use xdr_stream From: Chuck Lever To: linux-nfs@vger.kernel.org Date: Mon, 02 Jan 2023 12:06:03 -0500 Message-ID: <167267916310.112521.3610150780550171360.stgit@manet.1015granger.net> In-Reply-To: <167267753484.112521.4826748148788735127.stgit@manet.1015granger.net> References: <167267753484.112521.4826748148788735127.stgit@manet.1015granger.net> User-Agent: StGit/1.5.dev2+g9ce680a5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Chuck Lever Done as part of hardening the server-side RPC header decoding path. Signed-off-by: Chuck Lever --- net/sunrpc/svcauth_unix.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c index b6aef9c5113b..168e12137754 100644 --- a/net/sunrpc/svcauth_unix.c +++ b/net/sunrpc/svcauth_unix.c @@ -807,25 +807,41 @@ struct auth_ops svcauth_null = { }; +/** + * svcauth_tls_accept - Decode and validate incoming RPC_AUTH_TLS credential + * @rqstp: RPC transaction + * + * Return values: + * %SVC_OK: Both credential and verifier are valid + * %SVC_DENIED: Credential or verifier is not valid + * %SVC_GARBAGE: Failed to decode credential or verifier + * %SVC_CLOSE: Temporary failure + * + * rqstp->rq_auth_stat is set as mandated by RFC 5531. + */ static int svcauth_tls_accept(struct svc_rqst *rqstp) { + struct xdr_stream *xdr = &rqstp->rq_arg_stream; struct svc_cred *cred = &rqstp->rq_cred; - struct kvec *argv = rqstp->rq_arg.head; struct kvec *resv = rqstp->rq_res.head; + u32 flavor, len; + void *body; - if (argv->iov_len < XDR_UNIT * 3) - return SVC_GARBAGE; + svcxdr_init_decode(rqstp); - /* Call's cred length */ - if (svc_getu32(argv) != xdr_zero) { + /* Length of Call's credential body field: */ + if (xdr_stream_decode_u32(xdr, &len) < 0) + return SVC_GARBAGE; + if (len != 0) { rqstp->rq_auth_stat = rpc_autherr_badcred; return SVC_DENIED; } - /* Call's verifier flavor and its length */ - if (svc_getu32(argv) != rpc_auth_null || - svc_getu32(argv) != xdr_zero) { + /* Call's verf field: */ + if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0) + return SVC_GARBAGE; + if (flavor != RPC_AUTH_NULL || len != 0) { rqstp->rq_auth_stat = rpc_autherr_badverf; return SVC_DENIED; } @@ -836,12 +852,12 @@ svcauth_tls_accept(struct svc_rqst *rqstp) return SVC_DENIED; } - /* Mapping to nobody uid/gid is required */ + /* Signal that mapping to nobody uid/gid is required */ cred->cr_uid = INVALID_UID; cred->cr_gid = INVALID_GID; cred->cr_group_info = groups_alloc(0); if (cred->cr_group_info == NULL) - return SVC_CLOSE; /* kmalloc failure - client must retry */ + return SVC_CLOSE; /* Reply's verifier */ svc_putnl(resv, RPC_AUTH_NULL); @@ -853,7 +869,6 @@ svcauth_tls_accept(struct svc_rqst *rqstp) svc_putnl(resv, 0); rqstp->rq_cred.cr_flavor = RPC_AUTH_TLS; - svcxdr_init_decode(rqstp); return SVC_OK; }