From cfd278c280f997cf2fe4662e0acab0fe465f637b Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 19 Dec 2016 11:19:31 +1100 Subject: NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success. Various places assume that if nfs4_fl_prepare_ds() turns a non-NULL 'ds', then ds->ds_clp will also be non-NULL. This is not necessasrily true in the case when the process received a fatal signal while nfs4_pnfs_ds_connect is waiting in nfs4_wait_ds_connect(). In that case ->ds_clp may not be set, and the devid may not recently have been marked unavailable. So add a test for ds_clp == NULL and return NULL in that case. Fixes: c23266d532b4 ("NFS4.1 Fix data server connection race") Signed-off-by: NeilBrown Acked-by: Olga Kornievskaia Acked-by: Adamson, Andy Signed-off-by: Trond Myklebust --- fs/nfs/filelayout/filelayoutdev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/nfs/filelayout/filelayoutdev.c b/fs/nfs/filelayout/filelayoutdev.c index a5589b791439..f956ca20a8a3 100644 --- a/fs/nfs/filelayout/filelayoutdev.c +++ b/fs/nfs/filelayout/filelayoutdev.c @@ -282,7 +282,8 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx) s->nfs_client->cl_minorversion); out_test_devid: - if (filelayout_test_devid_unavailable(devid)) + if (ret->ds_clp == NULL || + filelayout_test_devid_unavailable(devid)) ret = NULL; out: return ret; -- cgit v1.2.3-59-g8ed1b