From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Mon, 19 Dec 2016 17:14:44 +0000 (-0500)
Subject: NFSv4: Place the GETATTR operation before the CLOSE
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d8d849835eb2082ea17655538a83fa467633927f;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

NFSv4: Place the GETATTR operation before the CLOSE

In order to benefit from the DENY share lock protection, we should
put the GETATTR operation before the CLOSE. Otherwise, we might race
with a Windows machine that thinks it is now safe to modify the file.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 872ff6756723..c3263114c6b8 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3147,7 +3147,7 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
 			res_stateid, calldata->arg.fmode);
 out_release:
 	nfs_release_seqid(calldata->arg.seqid);
-	nfs_refresh_inode(calldata->inode, calldata->res.fattr);
+	nfs_refresh_inode(calldata->inode, &calldata->fattr);
 	dprintk("%s: done, ret = %d!\n", __func__, task->tk_status);
 }
 
@@ -3215,7 +3215,10 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data)
 		nfs4_map_atomic_open_share(NFS_SERVER(inode),
 				calldata->arg.fmode, 0);
 
-	nfs_fattr_init(calldata->res.fattr);
+	if (calldata->res.fattr == NULL)
+		calldata->arg.bitmask = NULL;
+	else if (calldata->arg.bitmask == NULL)
+		calldata->res.fattr = NULL;
 	calldata->timestamp = jiffies;
 	if (nfs4_setup_sequence(NFS_SERVER(inode),
 				&calldata->arg.seq_args,
@@ -3282,6 +3285,7 @@ int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait)
 	calldata->arg.seqid = alloc_seqid(&state->owner->so_seqid, gfp_mask);
 	if (IS_ERR(calldata->arg.seqid))
 		goto out_free_calldata;
+	nfs_fattr_init(&calldata->fattr);
 	calldata->arg.fmode = 0;
 	calldata->lr.arg.ld_private = &calldata->lr.ld_private;
 	calldata->res.fattr = &calldata->fattr;
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 8ccb34cf0c19..6f2365b99fb4 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -2279,9 +2279,9 @@ static void nfs4_xdr_enc_close(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_putfh(xdr, args->fh, &hdr);
 	if (args->lr_args)
 		encode_layoutreturn(xdr, args->lr_args, &hdr);
-	encode_close(xdr, args, &hdr);
 	if (args->bitmask != NULL)
 		encode_getfattr(xdr, args->bitmask, &hdr);
+	encode_close(xdr, args, &hdr);
 	encode_nops(&hdr);
 }
 
@@ -6494,16 +6494,12 @@ static int nfs4_xdr_dec_close(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
 		if (status)
 			goto out;
 	}
+	if (res->fattr != NULL) {
+		status = decode_getfattr(xdr, res->fattr, res->server);
+		if (status != 0)
+			goto out;
+	}
 	status = decode_close(xdr, res);
-	if (status != 0)
-		goto out;
-	/*
-	 * Note: Server may do delete on close for this file
-	 * 	in which case the getattr call will fail with
-	 * 	an ESTALE error. Shouldn't be a problem,
-	 * 	though, since fattr->valid will remain unset.
-	 */
-	decode_getfattr(xdr, res->fattr, res->server);
 out:
 	return status;
 }