From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:50754 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933042AbcFCVjc (ORCPT ); Fri, 3 Jun 2016 17:39:32 -0400 From: Sasha Levin To: stable@vger.kernel.org, stable-commits@vger.kernel.org Cc: =?UTF-8?q?Tom=C3=A1=C5=A1=20Trnka?= , "J. Bruce Fields" , Sasha Levin Subject: [added to the 4.1 stable tree] sunrpc: fix stripping of padded MIC tokens Date: Fri, 3 Jun 2016 17:37:02 -0400 Message-Id: <1464989831-16666-127-git-send-email-sasha.levin@oracle.com> In-Reply-To: <1464989831-16666-1-git-send-email-sasha.levin@oracle.com> References: <1464989831-16666-1-git-send-email-sasha.levin@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: From: Tomáš Trnka This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit c0cb8bf3a8e4bd82e640862cdd8891400405cb89 ] The length of the GSS MIC token need not be a multiple of four bytes. It is then padded by XDR to a multiple of 4 B, but unwrap_integ_data() would previously only trim mic.len + 4 B. The remaining up to three bytes would then trigger a check in nfs4svc_decode_compoundargs(), leading to a "garbage args" error and mount failure: nfs4svc_decode_compoundargs: compound not properly padded! nfsd: failed to decode arguments! This would prevent older clients using the pre-RFC 4121 MIC format (37-byte MIC including a 9-byte OID) from mounting exports from v3.9+ servers using krb5i. The trimming was introduced by commit 4c190e2f913f ("sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer"). Fixes: 4c190e2f913f "unrpc: trim off trailing checksum..." Signed-off-by: Tomáš Trnka Cc: stable@vger.kernel.org Acked-by: Jeff Layton Signed-off-by: J. Bruce Fields Signed-off-by: Sasha Levin --- net/sunrpc/auth_gss/svcauth_gss.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 1095be9..4605dc7 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -857,8 +857,8 @@ unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct g goto out; if (svc_getnl(&buf->head[0]) != seq) goto out; - /* trim off the mic at the end before returning */ - xdr_buf_trim(buf, mic.len + 4); + /* trim off the mic and padding at the end before returning */ + xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4); stat = 0; out: kfree(mic.data); -- 2.5.0