NFSv4.1: Don't clobber the seqid if exchange_id returns a confirmed clientid

If the EXCHGID4_FLAG_CONFIRMED_R flag is set, the client is in theory
supposed to already know the correct value of the seqid, in which case
RFC5661 states that it should ignore the value returned.

Also ensure that if the sanity check in nfs4_check_cl_exchange_flags
fails, then we must not change the nfs_client fields.

Finally, clean up the code: we don't need to retest the value of
'status' unless it can change.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 485a6c0cdc409e0876709c1259ead4753c72877e..9f0a96fe621277a9be40c2e202faac797409ca3e 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5171,7 +5171,7 @@ int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
                .flags = EXCHGID4_FLAG_SUPP_MOVED_REFER,
        };
        struct nfs41_exchange_id_res res = {
-               .client = clp,
+               0
        };
        int status;
        struct rpc_message msg = {
@@ -5214,22 +5214,22 @@ int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
 
        status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
        if (status == 0)
-               status = nfs4_check_cl_exchange_flags(clp->cl_exchange_flags);
+               status = nfs4_check_cl_exchange_flags(res.flags);
 
        if (status == 0) {
+               clp->cl_clientid = res.clientid;
+               clp->cl_exchange_flags = (res.flags & ~EXCHGID4_FLAG_CONFIRMED_R);
+               if (!(res.flags & EXCHGID4_FLAG_CONFIRMED_R))
+                       clp->cl_seqid = res.seqid;
+
                kfree(clp->cl_serverowner);
                clp->cl_serverowner = res.server_owner;
                res.server_owner = NULL;
-       }
 
-       if (status == 0) {
                /* use the most recent implementation id */
                kfree(clp->cl_implid);
                clp->cl_implid = res.impl_id;
-       } else
-               kfree(res.impl_id);
 
-       if (status == 0) {
                if (clp->cl_serverscope != NULL &&
                    !nfs41_same_server_scope(clp->cl_serverscope,
                                             res.server_scope)) {
@@ -5244,7 +5244,8 @@ int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
                        clp->cl_serverscope = res.server_scope;
                        goto out;
                }
-       }
+       } else
+               kfree(res.impl_id);
 
 out_server_owner:
        kfree(res.server_owner);

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index b9ce3fdb862af8f76632ca22448b8f30af79a464..ee4a74db95d0b1b7ea49e8dd1263f0504f2fffa8 100644 (file)
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -5319,7 +5319,6 @@ static int decode_exchange_id(struct xdr_stream *xdr,
        uint32_t dummy;
        char *dummy_str;
        int status;
-       struct nfs_client *clp = res->client;
        uint32_t impl_id_count;
 
        status = decode_op_hdr(xdr, OP_EXCHANGE_ID);
@@ -5329,12 +5328,12 @@ static int decode_exchange_id(struct xdr_stream *xdr,
        p = xdr_inline_decode(xdr, 8);
        if (unlikely(!p))
                goto out_overflow;
-       xdr_decode_hyper(p, &clp->cl_clientid);
+       xdr_decode_hyper(p, &res->clientid);
        p = xdr_inline_decode(xdr, 12);
        if (unlikely(!p))
                goto out_overflow;
-       clp->cl_seqid = be32_to_cpup(p++);
-       clp->cl_exchange_flags = be32_to_cpup(p++);
+       res->seqid = be32_to_cpup(p++);
+       res->flags = be32_to_cpup(p++);
 
        /* We ask for SP4_NONE */
        dummy = be32_to_cpup(p);

diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 6387fc0097feb22c3703e6db193c21f02fcf4073..d1a7bf51c326dc7f103aae60874a667f3307b373 100644 (file)
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1132,7 +1132,8 @@ struct nfs41_bind_conn_to_session_res {
 };
 
 struct nfs41_exchange_id_res {
-       struct nfs_client               *client;
+       u64                             clientid;
+       u32                             seqid;
        u32                             flags;
        struct nfs41_server_owner       *server_owner;
        struct nfs41_server_scope       *server_scope;