From: J. Bruce Fields <bfields@redhat.com>
Date: Mon, 10 Oct 2011 21:34:31 +0000 (-0400)
Subject: nfsd4: ignore WANT bits in open downgrade
X-Git-Tag: firefly_0821_release~7541^2~2467
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0dc8985b7f2da02180135396871d396f33a39b43;p=firefly-linux-kernel-4.4.55.git

nfsd4: ignore WANT bits in open downgrade

commit c30e92df30d7d5fe65262fbce5d1b7de675fe34e upstream.

We don't use WANT bits yet--and sending them can probably trigger a
BUG() further down.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 3d893645cc69..ecd8152965ee 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3421,6 +3421,8 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp,
 	if (!access_valid(od->od_share_access, cstate->minorversion)
 			|| !deny_valid(od->od_share_deny))
 		return nfserr_inval;
+	/* We don't yet support WANT bits: */
+	od->od_share_access &= NFS4_SHARE_ACCESS_MASK;
 
 	nfs4_lock_state();
 	if ((status = nfs4_preprocess_seqid_op(cstate,