Use the EXCHGID4_FLAG_BIND_PRINC_STATEID exchange_id flag to enable stateid protection. This means that if we create a stateid using a particular principal, then we must use the same principal if we want to change that state. IOW: if we OPEN a file using a particular credential, then we have to use the same credential in subsequent OPEN_DOWNGRADE, CLOSE, or DELEGRETURN operations that use that stateid. Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> --- fs/nfs/nfs4proc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 7cdc706..3e21d43 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -5528,7 +5528,8 @@ int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred) struct nfs41_exchange_id_args args = { .verifier = &verifier, .client = clp, - .flags = EXCHGID4_FLAG_SUPP_MOVED_REFER, + .flags = EXCHGID4_FLAG_SUPP_MOVED_REFER | + EXCHGID4_FLAG_BIND_PRINC_STATEID, }; struct nfs41_exchange_id_res res = { 0 -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html