From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Scott Mayhew , "J. Bruce Fields" Subject: [PATCH 4.9 084/101] nfsd: restrict rd_maxcount to svc_max_payload in nfsd_encode_readdir Date: Sun, 1 Jul 2018 18:22:10 +0200 Message-Id: <20180701160800.521759316@linuxfoundation.org> In-Reply-To: <20180701160757.138608453@linuxfoundation.org> References: <20180701160757.138608453@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Scott Mayhew commit 9c2ece6ef67e9d376f32823086169b489c422ed0 upstream. nfsd4_readdir_rsize restricts rd_maxcount to svc_max_payload when estimating the size of the readdir reply, but nfsd_encode_readdir restricts it to INT_MAX when encoding the reply. This can result in log messages like "kernel: RPC request reserved 32896 but used 1049444". Restrict rd_dircount similarly (no reason it should be larger than svc_max_payload). Signed-off-by: Scott Mayhew Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4xdr.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3638,7 +3638,8 @@ nfsd4_encode_readdir(struct nfsd4_compou nfserr = nfserr_resource; goto err_no_verf; } - maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX); + maxcount = svc_max_payload(resp->rqstp); + maxcount = min_t(u32, readdir->rd_maxcount, maxcount); /* * Note the rfc defines rd_maxcount as the size of the * READDIR4resok structure, which includes the verifier above @@ -3652,7 +3653,7 @@ nfsd4_encode_readdir(struct nfsd4_compou /* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */ if (!readdir->rd_dircount) - readdir->rd_dircount = INT_MAX; + readdir->rd_dircount = svc_max_payload(resp->rqstp); readdir->xdr = xdr; readdir->rd_maxcount = maxcount;