When running LTP's nfslock01 test, the Linux client can send a LOCK and a FREE_STATEID request at the same time. The LOCK uses the same lockowner as the stateid sent in the FREE_STATEID request. The outcome is: Frame 115025 C FREE_STATEID stateid 2/A Frame 115026 C LOCK offset 672128 len 64 Frame 115029 R FREE_STATEID NFS4_OK Frame 115030 R LOCK stateid 3/A Frame 115034 C WRITE stateid 0/A offset 672128 len 64 Frame 115038 R WRITE NFS4ERR_BAD_STATEID In other words, the server returns stateid A in a successful LOCK reply, but it has already released it. Subsequent uses of the stateid fail. To address this, protect the generation check in nfsd4_free_stateid with the st_mutex. This should guarantee that only one of two outcomes occurs: either LOCK returns a fresh valid stateid, or FREE_STATEID returns NFS4ERR_LOCKS_HELD. Reported-by: Alexey Kodanev <alexey.kodanev@xxxxxxxxxx> Fix-suggested-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- fs/nfsd/nfs4state.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index b921123..07dc1aa 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4911,19 +4911,20 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, ret = nfserr_locks_held; break; case NFS4_LOCK_STID: + atomic_inc(&s->sc_count); + spin_unlock(&cl->cl_lock); + stp = openlockstateid(s); + mutex_lock(&stp->st_mutex); ret = check_stateid_generation(stateid, &s->sc_stateid, 1); if (ret) - break; - stp = openlockstateid(s); + goto out_mutex_unlock; ret = nfserr_locks_held; if (check_for_locks(stp->st_stid.sc_file, lockowner(stp->st_stateowner))) - break; - WARN_ON(!unhash_lock_stateid(stp)); - spin_unlock(&cl->cl_lock); - nfs4_put_stid(s); + goto out_mutex_unlock; + release_lock_stateid(stp); ret = nfs_ok; - goto out; + goto out_mutex_unlock; case NFS4_REVOKED_DELEG_STID: dp = delegstateid(s); list_del_init(&dp->dl_recall_lru); @@ -4937,6 +4938,10 @@ out_unlock: spin_unlock(&cl->cl_lock); out: return ret; +out_mutex_unlock: + mutex_unlock(&stp->st_mutex); + nfs4_put_stid(s); + goto out; } static inline int -- 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
