From 26c0c75e69265961e891ed80b38fb62a548ab371 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Sat, 24 Apr 2010 15:35:43 -0400 Subject: nfsd4: fix unlikely race in session replay case In the replay case, the renew_client(session->se_client); happens after we've droppped the sessionid_lock, and without holding a reference on the session; so there's nothing preventing the session being freed before we get here. Thanks to Benny Halevy for catching a bug in an earlier version of this patch. Signed-off-by: J. Bruce Fields Acked-by: Benny Halevy --- fs/nfsd/nfs4xdr.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'fs/nfsd/nfs4xdr.c') diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index fb27b1db007..05bc5bd63c9 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3306,10 +3306,12 @@ nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compo iov = &rqstp->rq_res.head[0]; iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base; BUG_ON(iov->iov_len > PAGE_SIZE); - if (nfsd4_has_session(cs) && cs->status != nfserr_replay_cache) { - nfsd4_store_cache_entry(resp); - dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__); - resp->cstate.slot->sl_inuse = false; + if (nfsd4_has_session(cs)) { + if (cs->status != nfserr_replay_cache) { + nfsd4_store_cache_entry(resp); + dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__); + resp->cstate.slot->sl_inuse = false; + } nfsd4_put_session(resp->cstate.session); } return 1; -- cgit v1.2.3-70-g09d2