Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ia0-f169.google.com ([209.85.210.169]:33651 "EHLO mail-ia0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755281Ab3A3Ted (ORCPT ); Wed, 30 Jan 2013 14:34:33 -0500 Received: by mail-ia0-f169.google.com with SMTP id j5so2848542iaf.14 for ; Wed, 30 Jan 2013 11:34:33 -0800 (PST) From: Chuck Lever Subject: [PATCH] SUNRPC: Pin GSS module while handling flavor lookups To: linux-nfs@vger.kernel.org Date: Wed, 30 Jan 2013 14:34:30 -0500 Message-ID: <20130130193120.1289.33936.stgit@seurat.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Add an API similar to rpcauth_lookup_pseudoflavor(). The NFS server should not call GSS API functions directly without first pinning the GSS module. Signed-off-by: Chuck Lever --- Bruce- Are you interested in taking something like this (untested) patch for 3.9? (This has pre-requisites I posted earlier this week). Not sure what to do about svcauth_gss_flavor(), which has the same issue. fs/nfsd/nfs4xdr.c | 18 ++++++++--------- include/linux/sunrpc/auth.h | 2 ++ include/linux/sunrpc/gss_api.h | 3 +++ net/sunrpc/auth.c | 35 +++++++++++++++++++++++++++++++++ net/sunrpc/auth_gss/auth_gss.c | 1 + net/sunrpc/auth_gss/gss_mech_switch.c | 31 +++++++++++++++++++++++++++++ 6 files changed, 80 insertions(+), 10 deletions(-) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 0dc1158..f986209 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3129,8 +3129,7 @@ static __be32 nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,struct svc_export *exp) { - int i = 0; - u32 nflavs; + u32 i, nflavs; struct exp_flavor_info *flavs; struct exp_flavor_info def_flavs[2]; __be32 *p; @@ -3162,23 +3161,22 @@ nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp, ADJUST_ARGS(); for (i = 0; i < nflavs; i++) { u32 flav = flavs[i].pseudoflavor; - struct gss_api_mech *gm = gss_mech_get_by_pseudoflavor(flav); + struct rpcsec_gss_info info; - if (gm) { + if (rpcauth_lookup_gss_info(flav, &info) == 0) { RESERVE_SPACE(4); WRITE32(RPC_AUTH_GSS); ADJUST_ARGS(); - RESERVE_SPACE(4 + gm->gm_oid.len); - WRITE32(gm->gm_oid.len); - WRITEMEM(gm->gm_oid.data, gm->gm_oid.len); + RESERVE_SPACE(4 + info.oid.len); + WRITE32(info.oid.len); + WRITEMEM(info.oid.data, info.oid.len); ADJUST_ARGS(); RESERVE_SPACE(4); - WRITE32(0); /* qop */ + WRITE32(info.qop); ADJUST_ARGS(); RESERVE_SPACE(4); - WRITE32(gss_pseudoflavor_to_service(gm, flav)); + WRITE32(info.service); ADJUST_ARGS(); - gss_mech_put(gm); } else { RESERVE_SPACE(4); WRITE32(flav); diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index b1a49a5..312684c 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -105,6 +105,7 @@ struct rpc_authops { void (*pipes_destroy)(struct rpc_auth *); int (*list_pseudoflavors)(rpc_authflavor_t *, int); rpc_authflavor_t (*lookup_pseudoflavor)(struct rpcsec_gss_info *); + int (*lookup_gss_info)(rpc_authflavor_t, struct rpcsec_gss_info *); }; struct rpc_credops { @@ -140,6 +141,7 @@ int rpcauth_unregister(const struct rpc_authops *); struct rpc_auth * rpcauth_create(rpc_authflavor_t, struct rpc_clnt *); void rpcauth_release(struct rpc_auth *); rpc_authflavor_t rpcauth_lookup_gss_pseudoflavor(struct rpcsec_gss_info *); +int rpcauth_lookup_gss_info(rpc_authflavor_t, struct rpcsec_gss_info *); int rpcauth_list_flavors(rpc_authflavor_t *, int); struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int); void rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *); diff --git a/include/linux/sunrpc/gss_api.h b/include/linux/sunrpc/gss_api.h index 6f40fd1..1293a7b 100644 --- a/include/linux/sunrpc/gss_api.h +++ b/include/linux/sunrpc/gss_api.h @@ -133,6 +133,9 @@ void gss_mech_unregister(struct gss_api_mech *); /* Given a GSS security tuple, look up a pseudoflavor */ rpc_authflavor_t gss_mech_lookup_pseudoflavor(struct rpcsec_gss_info *); +/* Given a pseudoflavor, look up a GSS security tuple */ +int gss_mech_lookup_info(rpc_authflavor_t, struct rpcsec_gss_info *); + /* Returns a reference to a mechanism, given a name like "krb5" etc. */ struct gss_api_mech *gss_mech_get_by_name(const char *); diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index 32e305b..0cfffbc 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -157,6 +157,41 @@ rpcauth_lookup_gss_pseudoflavor(struct rpcsec_gss_info *info) EXPORT_SYMBOL_GPL(rpcauth_lookup_gss_pseudoflavor); /** + * rpcauth_lookup_gss_info - find GSS tuple matching a pseudoflavor + * @pseudoflavor: GSS pseudoflavor to match + * @info: rpcsec_gss_info structure to fill in + * + * Returns zero and fills in "info" if pseudoflavor matches a + * supported mechanism. + */ +int +rpcauth_lookup_gss_info(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info) +{ + const struct rpc_authops *ops; + int result; + + if ((ops = auth_flavors[pseudoflavor]) == NULL) + request_module("rpc-auth-%u", RPC_AUTH_GSS); + spin_lock(&rpc_authflavor_lock); + ops = auth_flavors[pseudoflavor]; + if (ops == NULL || !try_module_get(ops->owner)) { + spin_unlock(&rpc_authflavor_lock); + dprintk("RPC: %s: failed to pin module\n", __func__); + return -ENOMEM; + } + spin_unlock(&rpc_authflavor_lock); + + if (ops->lookup_gss_info == NULL) + result = -ENOMEM; + else + result = ops->lookup_gss_info(pseudoflavor, info); + + module_put(ops->owner); + return result; +} +EXPORT_SYMBOL_GPL(rpcauth_lookup_gss_info); + +/** * rpcauth_list_flavors - discover registered flavors and pseudoflavors * @array: array to fill in * @size: size of "array" diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index f2e8f45..f1e92f4 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -1630,6 +1630,7 @@ static const struct rpc_authops authgss_ops = { .pipes_destroy = gss_pipes_dentries_destroy, .list_pseudoflavors = gss_mech_list_pseudoflavors, .lookup_pseudoflavor = gss_mech_lookup_pseudoflavor, + .lookup_gss_info = gss_mech_lookup_info, }; static const struct rpc_credops gss_credops = { diff --git a/net/sunrpc/auth_gss/gss_mech_switch.c b/net/sunrpc/auth_gss/gss_mech_switch.c index 3ba0450..7331b0b 100644 --- a/net/sunrpc/auth_gss/gss_mech_switch.c +++ b/net/sunrpc/auth_gss/gss_mech_switch.c @@ -314,6 +314,37 @@ rpc_authflavor_t gss_mech_lookup_pseudoflavor(struct rpcsec_gss_info *info) return pseudoflavor; } +/** + * gss_mech_lookup_info - look up a GSS tuple for a given pseudoflavor + * @pseudoflavor: GSS pseudoflavor to match + * @info: rpcsec_gss_info structure to fill in + * + * Returns zero and fills in "info" if pseudoflavor matches a + * supported mechanism. + */ +int gss_mech_lookup_info(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info) +{ + struct gss_api_mech *gm; + int i; + + gm = gss_mech_get_by_pseudoflavor(pseudoflavor); + if (gm == NULL) + return -ENOMEM; + + for (i = 0; i < gm->gm_pf_num; i++) + if (gm->gm_pfs[i].pseudoflavor == pseudoflavor) { + memcpy(info->oid.data, gm->gm_oid.data, gm->gm_oid.len); + info->oid.len = gm->gm_oid.len; + info->qop = gm->gm_pfs[i].qop; + info->service = gm->gm_pfs[i].service; + gss_mech_put(gm); + return 0; + } + + gss_mech_put(gm); + return -ENOMEM; +} + u32 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor) {