From 47ee52986472dba068e8223cbaf1b65d74238781 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Wed, 12 Mar 2014 21:39:35 -0400 Subject: [PATCH] nfsd4: adjust buflen to session channel limit We can simplify session limit enforcement by restricting the xdr buflen to the session size. Also fix a preexisting bug: we should really have been taking into account the auth-required space when comparing against session limits, which are limits on the size of the entire rpc reply, including any krb5 overhead. Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 11 +++++++++++ fs/nfsd/nfs4xdr.c | 24 ++++++++---------------- 2 files changed, 19 insertions(+), 16 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 8e22ea4..612b85a 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -2208,11 +2208,13 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_sequence *seq) { struct nfsd4_compoundres *resp = rqstp->rq_resp; + struct xdr_stream *xdr = &resp->xdr; struct nfsd4_session *session; struct nfs4_client *clp; struct nfsd4_slot *slot; struct nfsd4_conn *conn; __be32 status; + int buflen; struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); if (resp->opcnt != 1) @@ -2281,6 +2283,15 @@ nfsd4_sequence(struct svc_rqst *rqstp, if (status) goto out_put_session; + buflen = (seq->cachethis) ? + session->se_fchannel.maxresp_cached : + session->se_fchannel.maxresp_sz; + status = (seq->cachethis) ? nfserr_rep_too_big_to_cache : + nfserr_rep_too_big; + if (xdr_restrict_buflen(xdr, buflen - 2 * RPC_MAX_AUTH_SIZE)) + goto out_put_session; + + status = nfs_ok; /* Success! bump slot seqid */ slot->sl_seqid = seq->seqid; slot->sl_flags |= NFSD4_SLOT_INUSE; diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 1278d98..5e7bac4 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3767,25 +3767,17 @@ static nfsd4_enc nfsd4_enc_ops[] = { __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize) { struct xdr_buf *buf = &resp->rqstp->rq_res; - struct nfsd4_session *session = resp->cstate.session; + struct nfsd4_slot *slot = resp->cstate.slot; - if (nfsd4_has_session(&resp->cstate)) { - struct nfsd4_slot *slot = resp->cstate.slot; - - if (buf->len + respsize > session->se_fchannel.maxresp_sz) - return nfserr_rep_too_big; - - if ((slot->sl_flags & NFSD4_SLOT_CACHETHIS) && - buf->len + respsize > session->se_fchannel.maxresp_cached) - return nfserr_rep_too_big_to_cache; - } - - if (buf->len + respsize > buf->buflen) { - WARN_ON_ONCE(nfsd4_has_session(&resp->cstate)); + if (buf->len + respsize <= buf->buflen) + return nfs_ok; + if (!nfsd4_has_session(&resp->cstate)) return nfserr_resource; + if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) { + WARN_ON_ONCE(1); + return nfserr_rep_too_big_to_cache; } - - return 0; + return nfserr_rep_too_big; } void -- 2.7.4