| From | Jiri Slaby <> | Subject | [PATCH 3.12 168/235] NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success. | Date | Fri, 27 Jan 2017 11:55:01 +0100 |
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From: NeilBrown <neilb@suse.com>
3.12-stable review patch. If anyone has any objections, please let me know.
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commit cfd278c280f997cf2fe4662e0acab0fe465f637b upstream.
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 <neilb@suse.com> Acked-by: Olga Kornievskaia <aglo@umich.edu> Acked-by: Adamson, Andy <William.Adamson@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> --- fs/nfs/nfs4filelayoutdev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c index efac602edb37..91de91430b31 100644 --- a/fs/nfs/nfs4filelayoutdev.c +++ b/fs/nfs/nfs4filelayoutdev.c @@ -827,7 +827,8 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx) nfs4_wait_ds_connect(ds); } out_test_devid: - if (filelayout_test_devid_unavailable(devid)) + if (ret->ds_clp == NULL || + filelayout_test_devid_unavailable(devid)) ret = NULL; out: return ret; -- 2.11.0
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