diff mbox series

[RFC,15/21] NFSD: Add nfsd_clid_verf_mismatch tracepoint

Message ID 162066199008.94415.3881243902817026664.stgit@klimt.1015granger.net (mailing list archive)
State New
Headers show
Series NFSD callback and lease management observability | expand

Commit Message

Chuck Lever III May 10, 2021, 3:53 p.m. UTC
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>
---
 fs/nfsd/nfs4state.c |   11 ++++++++---
 fs/nfsd/trace.h     |   32 ++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 3 deletions(-)

Comments

Bruce Fields May 11, 2021, 3:49 p.m. UTC | #1
On Mon, May 10, 2021 at 11:53:10AM -0400, Chuck Lever wrote:
> 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.

Yes.  I suspect this is much more common that the cred mismatch case,
unfortunately.  Without kerberos, we just don't have much to go
on--we're not supposed to use IP address, and the auth_unix cred itself
probably doesn't vary much across clients.

(Patch looks fine, just commenting on that because it's a confusing
point.)

--b.

> 
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> ---
>  fs/nfsd/nfs4state.c |   11 ++++++++---
>  fs/nfsd/trace.h     |   32 ++++++++++++++++++++++++++++++++
>  2 files changed, 40 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 4feadb683a2d..56ca79f55da4 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -3193,6 +3193,7 @@ 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;
>  	}
> @@ -3988,9 +3989,13 @@ 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 80fd6ca6ae46..2c0392f30a86 100644
> --- a/fs/nfsd/trace.h
> +++ b/fs/nfsd/trace.h
> @@ -592,6 +592,38 @@ 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),
>
diff mbox series

Patch

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 4feadb683a2d..56ca79f55da4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3193,6 +3193,7 @@  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;
 	}
@@ -3988,9 +3989,13 @@  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 80fd6ca6ae46..2c0392f30a86 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -592,6 +592,38 @@  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),