linux-kernel - [PATCH 7/7] nfsd: drop unnecessary MAY

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Date:	Fri, 22 Jul 2016 13:48:56 -0400
From:	"J. Bruce Fields" <bfields@...hat.com>
To:	Oleg Drokin <green@...uxhacker.ru>
Cc:	Jeff Layton <jlayton@...chiereds.net>, linux-nfs@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	"J. Bruce Fields" <bfields@...ldses.org>,
	"J. Bruce Fields" <bfields@...hat.com>
Subject: [PATCH 7/7] nfsd: drop unnecessary MAY_EXEC check from create

From: "J. Bruce Fields" <bfields@...hat.com>

We need an fh_verify to make sure we at least have a dentry, but actual
permission checks happen later.

Signed-off-by: J. Bruce Fields <bfields@...hat.com>
---
 fs/nfsd/nfs4proc.c | 7 +------
 fs/nfsd/vfs.c      | 6 +-----
 2 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 9d7e1edf0cca..1fb222752b2b 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -605,12 +605,7 @@ nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 
 	fh_init(&resfh, NFS4_FHSIZE);
 
-	/*
-	 * We just check that parent is accessible here, nfsd_* do their
-	 * own access permission checks
-	 */
-	status = fh_verify(rqstp, &cstate->current_fh, S_IFDIR,
-			   NFSD_MAY_EXEC);
+	status = fh_verify(rqstp, &cstate->current_fh, S_IFDIR, NFSD_MAY_NOP);
 	if (status)
 		return status;
 
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index cd06c6511cfc..c844fd601381 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1236,11 +1236,7 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (isdotent(fname, flen))
 		return nfserr_exist;
 
-	/*
-	 * Even though it is a create, first let's see if we are even allowed
-	 * to peek inside the parent
-	 */
-	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
+	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_NOP);
 	if (err)
 		return err;
 
-- 
2.7.4