NFSD: Add nfsd_clid_verf_mismatch tracepoint

Record when a client presents a different boot verifier than the
one we know about. Typically this is a sign the client has
rebooted, but sometimes it signals a conflicting client ID, which
the client's administrator will need to address.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 84c4021..69405cc 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3191,6 +3191,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                        goto out_copy;
                }
                /* case 5, client reboot */
+               trace_nfsd_clid_verf_mismatch(conf, rqstp, &verf);
                conf = NULL;
                goto out_new;
        }
@@ -3986,9 +3987,13 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
        if (unconf)
                unhash_client_locked(unconf);
        /* We need to handle only case 1: probable callback update */
-       if (conf && same_verf(&conf->cl_verifier, &clverifier)) {
-               copy_clid(new, conf);
-               gen_confirm(new, nn);
+       if (conf) {
+               if (same_verf(&conf->cl_verifier, &clverifier)) {
+                       copy_clid(new, conf);
+                       gen_confirm(new, nn);
+               } else
+                       trace_nfsd_clid_verf_mismatch(conf, rqstp,
+                                                     &clverifier);
        }
        new->cl_minorversion = 0;
        gen_callback(new, setclid, rqstp);

diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 820a542..24f54ab 100644 (file)
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -564,6 +564,38 @@ TRACE_EVENT(nfsd_clid_cred_mismatch,
        )
 )
 
+TRACE_EVENT(nfsd_clid_verf_mismatch,
+       TP_PROTO(
+               const struct nfs4_client *clp,
+               const struct svc_rqst *rqstp,
+               const nfs4_verifier *verf
+       ),
+       TP_ARGS(clp, rqstp, verf),
+       TP_STRUCT__entry(
+               __field(u32, cl_boot)
+               __field(u32, cl_id)
+               __array(unsigned char, cl_verifier, NFS4_VERIFIER_SIZE)
+               __array(unsigned char, new_verifier, NFS4_VERIFIER_SIZE)
+               __array(unsigned char, addr, sizeof(struct sockaddr_in6))
+       ),
+       TP_fast_assign(
+               __entry->cl_boot = clp->cl_clientid.cl_boot;
+               __entry->cl_id = clp->cl_clientid.cl_id;
+               memcpy(__entry->cl_verifier, (void *)&clp->cl_verifier,
+                      NFS4_VERIFIER_SIZE);
+               memcpy(__entry->new_verifier, (void *)verf,
+                      NFS4_VERIFIER_SIZE);
+               memcpy(__entry->addr, &rqstp->rq_xprt->xpt_remote,
+                       sizeof(struct sockaddr_in6));
+       ),
+       TP_printk("client %08x:%08x verf=0x%s, updated=0x%s from addr=%pISpc",
+               __entry->cl_boot, __entry->cl_id,
+               __print_hex_str(__entry->cl_verifier, NFS4_VERIFIER_SIZE),
+               __print_hex_str(__entry->new_verifier, NFS4_VERIFIER_SIZE),
+               __entry->addr
+       )
+);
+
 TRACE_EVENT(nfsd_clid_inuse_err,
        TP_PROTO(const struct nfs4_client *clp),
        TP_ARGS(clp),