From 8e5b67731d088e66fc6a59d9e2fc9a5e4e187303 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 9 Apr 2019 11:46:15 -0400 Subject: SUNRPC: Add a callback to initialise server requests Add a callback to help initialise server requests before they are processed. This will allow us to clean up the NFS server version support, and to make it container safe. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields --- net/sunrpc/svc.c | 113 +++++++++++++++++++++++++++++++++++++------------------ 1 file changed, 76 insertions(+), 37 deletions(-) (limited to 'net') diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 3d5dd6b86652..69f3b9e015ce 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1160,6 +1160,59 @@ svc_get_autherr(struct svc_rqst *rqstp, __be32 *statp) return rpc_auth_ok; } +__be32 +svc_generic_init_request(struct svc_rqst *rqstp, + const struct svc_program *progp, + struct svc_process_info *ret) +{ + const struct svc_version *versp = NULL; /* compiler food */ + const struct svc_procedure *procp = NULL; + + if (rqstp->rq_vers >= progp->pg_nvers ) + goto err_bad_vers; + versp = progp->pg_vers[rqstp->rq_vers]; + if (!versp) + goto err_bad_vers; + + /* + * Some protocol versions (namely NFSv4) require some form of + * congestion control. (See RFC 7530 section 3.1 paragraph 2) + * In other words, UDP is not allowed. We mark those when setting + * up the svc_xprt, and verify that here. + * + * The spec is not very clear about what error should be returned + * when someone tries to access a server that is listening on UDP + * for lower versions. RPC_PROG_MISMATCH seems to be the closest + * fit. + */ + if (versp->vs_need_cong_ctrl && rqstp->rq_xprt && + !test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags)) + goto err_bad_vers; + + if (rqstp->rq_proc >= versp->vs_nproc) + goto err_bad_proc; + rqstp->rq_procinfo = procp = &versp->vs_proc[rqstp->rq_proc]; + if (!procp) + goto err_bad_proc; + + /* Initialize storage for argp and resp */ + memset(rqstp->rq_argp, 0, procp->pc_argsize); + memset(rqstp->rq_resp, 0, procp->pc_ressize); + + /* Bump per-procedure stats counter */ + versp->vs_count[rqstp->rq_proc]++; + + ret->dispatch = versp->vs_dispatch; + return rpc_success; +err_bad_vers: + ret->mismatch.lovers = progp->pg_lovers; + ret->mismatch.hivers = progp->pg_hivers; + return rpc_prog_mismatch; +err_bad_proc: + return rpc_proc_unavail; +} +EXPORT_SYMBOL_GPL(svc_generic_init_request); + /* * Common routine for processing the RPC request. */ @@ -1167,11 +1220,11 @@ static int svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) { struct svc_program *progp; - const struct svc_version *versp = NULL; /* compiler food */ const struct svc_procedure *procp = NULL; struct svc_serv *serv = rqstp->rq_server; + struct svc_process_info process; __be32 *statp; - u32 prog, vers, proc; + u32 prog, vers; __be32 auth_stat, rpc_stat; int auth_res; __be32 *reply_statp; @@ -1203,8 +1256,8 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) svc_putnl(resv, 0); /* ACCEPT */ rqstp->rq_prog = prog = svc_getnl(argv); /* program number */ - rqstp->rq_vers = vers = svc_getnl(argv); /* version number */ - rqstp->rq_proc = proc = svc_getnl(argv); /* procedure number */ + rqstp->rq_vers = svc_getnl(argv); /* version number */ + rqstp->rq_proc = svc_getnl(argv); /* procedure number */ for (progp = serv->sv_program; progp; progp = progp->pg_next) if (prog == progp->pg_prog) @@ -1242,29 +1295,22 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) if (progp == NULL) goto err_bad_prog; - if (vers >= progp->pg_nvers || - !(versp = progp->pg_vers[vers])) - goto err_bad_vers; - - /* - * Some protocol versions (namely NFSv4) require some form of - * congestion control. (See RFC 7530 section 3.1 paragraph 2) - * In other words, UDP is not allowed. We mark those when setting - * up the svc_xprt, and verify that here. - * - * The spec is not very clear about what error should be returned - * when someone tries to access a server that is listening on UDP - * for lower versions. RPC_PROG_MISMATCH seems to be the closest - * fit. - */ - if (versp->vs_need_cong_ctrl && rqstp->rq_xprt && - !test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags)) + rpc_stat = progp->pg_init_request(rqstp, progp, &process); + switch (rpc_stat) { + case rpc_success: + break; + case rpc_prog_unavail: + goto err_bad_prog; + case rpc_prog_mismatch: goto err_bad_vers; + case rpc_proc_unavail: + goto err_bad_proc; + } - procp = versp->vs_proc + proc; - if (proc >= versp->vs_nproc || !procp->pc_func) + procp = rqstp->rq_procinfo; + /* Should this check go into the dispatcher? */ + if (!procp || !procp->pc_func) goto err_bad_proc; - rqstp->rq_procinfo = procp; /* Syntactic check complete */ serv->sv_stats->rpccnt++; @@ -1274,13 +1320,6 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) statp = resv->iov_base +resv->iov_len; svc_putnl(resv, RPC_SUCCESS); - /* Bump per-procedure stats counter */ - versp->vs_count[proc]++; - - /* Initialize storage for argp and resp */ - memset(rqstp->rq_argp, 0, procp->pc_argsize); - memset(rqstp->rq_resp, 0, procp->pc_ressize); - /* un-reserve some of the out-queue now that we have a * better idea of reply size */ @@ -1288,7 +1327,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) svc_reserve_auth(rqstp, procp->pc_xdrressize<<2); /* Call the function that processes the request. */ - if (!versp->vs_dispatch) { + if (!process.dispatch) { /* * Decode arguments * XXX: why do we ignore the return value? @@ -1317,7 +1356,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) } } else { dprintk("svc: calling dispatcher\n"); - if (!versp->vs_dispatch(rqstp, statp)) { + if (!process.dispatch(rqstp, statp)) { /* Release reply info */ if (procp->pc_release) procp->pc_release(rqstp); @@ -1386,16 +1425,16 @@ err_bad_prog: err_bad_vers: svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n", - vers, prog, progp->pg_name); + rqstp->rq_vers, rqstp->rq_prog, progp->pg_name); serv->sv_stats->rpcbadfmt++; svc_putnl(resv, RPC_PROG_MISMATCH); - svc_putnl(resv, progp->pg_lovers); - svc_putnl(resv, progp->pg_hivers); + svc_putnl(resv, process.mismatch.lovers); + svc_putnl(resv, process.mismatch.hivers); goto sendit; err_bad_proc: - svc_printk(rqstp, "unknown procedure (%d)\n", proc); + svc_printk(rqstp, "unknown procedure (%d)\n", rqstp->rq_proc); serv->sv_stats->rpcbadfmt++; svc_putnl(resv, RPC_PROC_UNAVAIL); -- cgit