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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT 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 21B7BC43381 for ; Tue, 19 Feb 2019 21:38:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ECFA52086D for ; Tue, 19 Feb 2019 21:38:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726451AbfBSViE (ORCPT ); Tue, 19 Feb 2019 16:38:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47634 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728169AbfBSViE (ORCPT ); Tue, 19 Feb 2019 16:38:04 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B6A76B212 for ; Tue, 19 Feb 2019 21:38:03 +0000 (UTC) Received: from parsley.fieldses.org (ovpn-123-19.rdu2.redhat.com [10.10.123.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4FFBF5DD63; Tue, 19 Feb 2019 21:38:03 +0000 (UTC) Received: by parsley.fieldses.org (Postfix, from userid 2815) id 42F5E18036E; Tue, 19 Feb 2019 16:38:02 -0500 (EST) Date: Tue, 19 Feb 2019 16:38:02 -0500 From: "J. Bruce Fields" To: Scott Mayhew Cc: stable@vger.kernel.org Subject: Re: [PATCH 4.19] sunrpc: fix 4 more call sites that were using stack memory with a scatterlist Message-ID: <20190219213801.GC26296@parsley.fieldses.org> References: <20190219193627.15619-1-smayhew@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190219193627.15619-1-smayhew@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 19 Feb 2019 21:38:03 +0000 (UTC) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org ACK.--b. On Tue, Feb 19, 2019 at 02:36:27PM -0500, Scott Mayhew wrote: > (cherry picked from commit e7afe6c1d486b516ed586dcc10b3e7e3e85a9c2b) > > While trying to reproduce a reported kernel panic on arm64, I discovered > that AUTH_GSS basically doesn't work at all with older enctypes on arm64 > systems with CONFIG_VMAP_STACK enabled. It turns out there still a few > places using stack memory with scatterlists, causing krb5_encrypt() and > krb5_decrypt() to produce incorrect results (or a BUG if CONFIG_DEBUG_SG > is enabled). > > Tested with cthon on v4.0/v4.1/v4.2 with krb5/krb5i/krb5p using > des3-cbc-sha1 and arcfour-hmac-md5. > > Signed-off-by: Scott Mayhew > Cc: stable@vger.kernel.org > Signed-off-by: J. Bruce Fields > > Conflicts: > net/sunrpc/auth_gss/gss_krb5_seqnum.c > --- > net/sunrpc/auth_gss/gss_krb5_seqnum.c | 49 +++++++++++++++++++++++++++-------- > 1 file changed, 38 insertions(+), 11 deletions(-) > > diff --git a/net/sunrpc/auth_gss/gss_krb5_seqnum.c b/net/sunrpc/auth_gss/gss_krb5_seqnum.c > index c8b9082..2d2ed67 100644 > --- a/net/sunrpc/auth_gss/gss_krb5_seqnum.c > +++ b/net/sunrpc/auth_gss/gss_krb5_seqnum.c > @@ -44,7 +44,7 @@ > unsigned char *cksum, unsigned char *buf) > { > struct crypto_skcipher *cipher; > - unsigned char plain[8]; > + unsigned char *plain; > s32 code; > > dprintk("RPC: %s:\n", __func__); > @@ -53,6 +53,10 @@ > if (IS_ERR(cipher)) > return PTR_ERR(cipher); > > + plain = kmalloc(8, GFP_NOFS); > + if (!plain) > + return -ENOMEM; > + > plain[0] = (unsigned char) ((seqnum >> 24) & 0xff); > plain[1] = (unsigned char) ((seqnum >> 16) & 0xff); > plain[2] = (unsigned char) ((seqnum >> 8) & 0xff); > @@ -69,6 +73,7 @@ > code = krb5_encrypt(cipher, cksum, plain, buf, 8); > out: > crypto_free_skcipher(cipher); > + kfree(plain); > return code; > } > s32 > @@ -78,12 +83,17 @@ > u32 seqnum, > unsigned char *cksum, unsigned char *buf) > { > - unsigned char plain[8]; > + unsigned char *plain; > + s32 code; > > if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) > return krb5_make_rc4_seq_num(kctx, direction, seqnum, > cksum, buf); > > + plain = kmalloc(8, GFP_NOFS); > + if (!plain) > + return -ENOMEM; > + > plain[0] = (unsigned char) (seqnum & 0xff); > plain[1] = (unsigned char) ((seqnum >> 8) & 0xff); > plain[2] = (unsigned char) ((seqnum >> 16) & 0xff); > @@ -94,7 +104,9 @@ > plain[6] = direction; > plain[7] = direction; > > - return krb5_encrypt(key, cksum, plain, buf, 8); > + code = krb5_encrypt(key, cksum, plain, buf, 8); > + kfree(plain); > + return code; > } > > static s32 > @@ -102,7 +114,7 @@ > unsigned char *buf, int *direction, s32 *seqnum) > { > struct crypto_skcipher *cipher; > - unsigned char plain[8]; > + unsigned char *plain; > s32 code; > > dprintk("RPC: %s:\n", __func__); > @@ -115,20 +127,28 @@ > if (code) > goto out; > > + plain = kmalloc(8, GFP_NOFS); > + if (!plain) { > + code = -ENOMEM; > + goto out; > + } > + > code = krb5_decrypt(cipher, cksum, buf, plain, 8); > if (code) > - goto out; > + goto out_plain; > > if ((plain[4] != plain[5]) || (plain[4] != plain[6]) > || (plain[4] != plain[7])) { > code = (s32)KG_BAD_SEQ; > - goto out; > + goto out_plain; > } > > *direction = plain[4]; > > *seqnum = ((plain[0] << 24) | (plain[1] << 16) | > (plain[2] << 8) | (plain[3])); > +out_plain: > + kfree(plain); > out: > crypto_free_skcipher(cipher); > return code; > @@ -141,26 +161,33 @@ > int *direction, u32 *seqnum) > { > s32 code; > - unsigned char plain[8]; > struct crypto_skcipher *key = kctx->seq; > + unsigned char *plain; > > dprintk("RPC: krb5_get_seq_num:\n"); > > if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) > return krb5_get_rc4_seq_num(kctx, cksum, buf, > direction, seqnum); > + plain = kmalloc(8, GFP_NOFS); > + if (!plain) > + return -ENOMEM; > > if ((code = krb5_decrypt(key, cksum, buf, plain, 8))) > - return code; > + goto out; > > if ((plain[4] != plain[5]) || (plain[4] != plain[6]) || > - (plain[4] != plain[7])) > - return (s32)KG_BAD_SEQ; > + (plain[4] != plain[7])) { > + code = (s32)KG_BAD_SEQ; > + goto out; > + } > > *direction = plain[4]; > > *seqnum = ((plain[0]) | > (plain[1] << 8) | (plain[2] << 16) | (plain[3] << 24)); > > - return 0; > +out: > + kfree(plain); > + return code; > } > -- > 1.8.3.1 >