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 <trond.myklebust@xxxxxxxxxxxxxxx>
---
fs/lockd/svc.c | 3 +-
fs/nfs/callback.c | 1 +
fs/nfsd/nfssvc.c | 2 +
include/linux/sunrpc/svc.h | 16 +++++
net/sunrpc/svc.c | 125 ++++++++++++++++++++++++-------------
5 files changed, 103 insertions(+), 44 deletions(-)
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 346ed161756d..75415b21efda 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -807,5 +807,6 @@ static struct svc_program nlmsvc_program = {
.pg_name = "lockd", /* service name */
.pg_class = "nfsd", /* share authentication with nfsd */
.pg_stats = &nlmsvc_stats, /* stats table */
- .pg_authenticate = &lockd_authenticate /* export authentication */
+ .pg_authenticate = &lockd_authenticate, /* export authentication */
+ .pg_init_request = svc_generic_init_request,
};
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 0b602a39dd71..a9510374bad7 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -457,4 +457,5 @@ static struct svc_program nfs4_callback_program = {
.pg_class = "nfs", /* authentication class */
.pg_stats = &nfs4_callback_stats,
.pg_authenticate = nfs_callback_authenticate,
+ .pg_init_request = svc_generic_init_request,
};
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 89cb484f1cfb..e26762e84798 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -86,6 +86,7 @@ static struct svc_program nfsd_acl_program = {
.pg_class = "nfsd",
.pg_stats = &nfsd_acl_svcstats,
.pg_authenticate = &svc_set_client,
+ .pg_init_request = svc_generic_init_request,
};
static struct svc_stat nfsd_acl_svcstats = {
@@ -118,6 +119,7 @@ struct svc_program nfsd_program = {
.pg_class = "nfsd", /* authentication class */
.pg_stats = &nfsd_svcstats, /* version table */
.pg_authenticate = &svc_set_client, /* export authentication */
+ .pg_init_request = svc_generic_init_request,
};
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 7ff12c9dbeaf..f43d5765acff 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -383,6 +383,16 @@ struct svc_deferred_req {
__be32 args[0];
};
+struct svc_process_info {
+ union {
+ int (*dispatch)(struct svc_rqst *, __be32 *);
+ struct {
+ unsigned int lovers;
+ unsigned int hivers;
+ } mismatch;
+ };
+};
+
/*
* List of RPC programs on the same transport endpoint
*/
@@ -397,6 +407,9 @@ struct svc_program {
char * pg_class; /* class name: services sharing authentication */
struct svc_stat * pg_stats; /* rpc statistics */
int (*pg_authenticate)(struct svc_rqst *);
+ __be32 (*pg_init_request)(struct svc_rqst *,
+ const struct svc_program *,
+ struct svc_process_info *);
};
/*
@@ -506,6 +519,9 @@ char *svc_fill_symlink_pathname(struct svc_rqst *rqstp,
struct kvec *first, void *p,
size_t total);
__be32 svc_return_autherr(struct svc_rqst *rqstp, __be32 auth_err);
+__be32 svc_generic_init_request(struct svc_rqst *rqstp,
+ const struct svc_program *progp,
+ struct svc_process_info *procinfo);
#define RPC_MAX_ADDRBUFLEN (63U)
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 3d5dd6b86652..5f87c0f1e4e0 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1160,6 +1160,65 @@ 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);
+
+ /* un-reserve some of the out-queue now that we have a
+ * better idea of reply size
+ */
+ if (procp->pc_xdrressize)
+ svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
+
+ /* 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 +1226,11 @@ 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 +1262,8 @@ 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 +1301,22 @@ 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++;
@@ -1274,21 +1326,8 @@ 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
- */
- if (procp->pc_xdrressize)
- 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 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
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);
--
2.20.1
