NFS: Fix following referral mount points with different security

I create a new proc_lookup_mountpoint() to use when submounting an NFS v4 share. This function returns an rpc_clnt to use for performing an fs_locations() call on a referral's mountpoint. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Fix following referral mount points with different security
I create a new proc_lookup_mountpoint() to use when submounting an NFS v4 share. This function returns an rpc_clnt to use for performing an fs_locations() call on a referral's mountpoint. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Bryan Schumaker · Trond Myklebust
1 parent 72de53ec4b
Showing 5 changed files with 72 additions and 26 deletions Side-by-side Diff
fs/nfs/internal.h
fs/nfs/namespace.c
fs/nfs/nfs4_fs.h
fs/nfs/nfs4namespace.c
fs/nfs/nfs4proc.c
@@ -186,10 +186,10 @@
  
 /* nfs4namespace.c */
 #ifdef CONFIG_NFS_V4
-extern struct vfsmount *nfs_do_refmount(struct dentry *dentry);
+extern struct vfsmount *nfs_do_refmount(struct rpc_clnt *client, struct dentry *dentry);
 #else
 static inline
-struct vfsmount *nfs_do_refmount(struct dentry *dentry)
+struct vfsmount *nfs_do_refmount(struct rpc_clnt *client, struct dentry *dentry)
 {
 	return ERR_PTR(-ENOENT);
 }
@@ -200,6 +200,22 @@
 out:
 	return err;
 }
+
+static struct rpc_clnt *nfs_lookup_mountpoint(struct inode *dir,
+					      struct qstr *name,
+					      struct nfs_fh *fh,
+					      struct nfs_fattr *fattr)
+{
+	int err;
+
+	if (NFS_PROTO(dir)->version == 4)
+		return nfs4_proc_lookup_mountpoint(dir, name, fh, fattr);
+
+	err = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, name, fh, fattr);
+	if (err)
+		return ERR_PTR(err);
+	return rpc_clone_client(NFS_SERVER(dir)->client);
+}
 #else /* CONFIG_NFS_V4 */
 static inline int nfs_lookup_with_sec(struct nfs_server *server,
 				      struct dentry *parent, struct dentry *dentry,
@@ -209,6 +225,17 @@
 {
 	return -EPERM;
 }
+
+static inline struct rpc_clnt *nfs_lookup_mountpoint(struct inode *dir,
+						     struct qstr *name,
+						     struct nfs_fh *fh,
+						     struct nfs_fattr *fattr)
+{
+	int err = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, name, fh, fattr);
+	if (err)
+		return ERR_PTR(err);
+	return rpc_clone_client(NFS_SERVER(dir)->client);
+}
 #endif /* CONFIG_NFS_V4 */
  
 /*
  
@@ -226,11 +253,10 @@
 struct vfsmount *nfs_d_automount(struct path *path)
 {
 	struct vfsmount *mnt;
-	struct nfs_server *server = NFS_SERVER(path->dentry->d_inode);
 	struct dentry *parent;
 	struct nfs_fh *fh = NULL;
 	struct nfs_fattr *fattr = NULL;
-	int err;
+	struct rpc_clnt *client;
 	rpc_authflavor_t flavor = RPC_AUTH_UNIX;
  
 	dprintk("--> nfs_d_automount()\n");
  
  
  
@@ -249,21 +275,19 @@
  
 	/* Look it up again to get its attributes */
 	parent = dget_parent(path->dentry);
-	err = server->nfs_client->rpc_ops->lookup(server->client, parent->d_inode,
-						  &path->dentry->d_name,
-						  fh, fattr);
-	if (err == -EPERM && NFS_PROTO(parent->d_inode)->secinfo != NULL)
-		err = nfs_lookup_with_sec(server, parent, path->dentry, path, fh, fattr, &flavor);
+	client = nfs_lookup_mountpoint(parent->d_inode, &path->dentry->d_name, fh, fattr);
 	dput(parent);
-	if (err != 0) {
-		mnt = ERR_PTR(err);
+	if (IS_ERR(client)) {
+		mnt = ERR_CAST(client);
 		goto out;
 	}
  
 	if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
-		mnt = nfs_do_refmount(path->dentry);
+		mnt = nfs_do_refmount(client, path->dentry);
 	else
 		mnt = nfs_do_submount(path->dentry, fh, fattr, flavor);
+	rpc_shutdown_client(client);
+
 	if (IS_ERR(mnt))
 		goto out;
  
@@ -216,8 +216,10 @@
 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait, bool roc);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
-extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
-		struct nfs4_fs_locations *fs_locations, struct page *page);
+extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
+				  struct nfs4_fs_locations *, struct page *);
+extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
+			    struct nfs_fh *, struct nfs_fattr *);
 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 extern int nfs4_release_lockowner(struct nfs4_lock_state *);
 extern const struct xattr_handler *nfs4_xattr_handlers[];
@@ -300,7 +300,7 @@
  * @dentry - dentry of referral
  *
  */
-struct vfsmount *nfs_do_refmount(struct dentry *dentry)
+struct vfsmount *nfs_do_refmount(struct rpc_clnt *client, struct dentry *dentry)
 {
 	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
 	struct dentry *parent;
@@ -326,7 +326,7 @@
 	dprintk("%s: getting locations for %s/%s\n",
 		__func__, parent->d_name.name, dentry->d_name.name);
  
-	err = nfs4_proc_fs_locations(parent->d_inode, &dentry->d_name, fs_locations, page);
+	err = nfs4_proc_fs_locations(client, parent->d_inode, &dentry->d_name, fs_locations, page);
 	dput(parent);
 	if (err != 0 ||
 	    fs_locations->nlocations <= 0 ||
@@ -2377,8 +2377,9 @@
  * Note that we'll actually follow the referral later when
  * we detect fsid mismatch in inode revalidation
  */
-static int nfs4_get_referral(struct inode *dir, const struct qstr *name,
-			     struct nfs_fattr *fattr, struct nfs_fh *fhandle)
+static int nfs4_get_referral(struct rpc_clnt *client, struct inode *dir,
+			     const struct qstr *name, struct nfs_fattr *fattr,
+			     struct nfs_fh *fhandle)
 {
 	int status = -ENOMEM;
 	struct page *page = NULL;
@@ -2391,7 +2392,7 @@
 	if (locations == NULL)
 		goto out;
  
-	status = nfs4_proc_fs_locations(dir, name, locations, page);
+	status = nfs4_proc_fs_locations(client, dir, name, locations, page);
 	if (status != 0)
 		goto out;
 	/* Make sure server returned a different fsid for the referral */
@@ -2550,7 +2551,7 @@
 			err = -ENOENT;
 			goto out;
 		case -NFS4ERR_MOVED:
-			err = nfs4_get_referral(dir, name, fattr, fhandle);
+			err = nfs4_get_referral(client, dir, name, fattr, fhandle);
 			goto out;
 		case -NFS4ERR_WRONGSEC:
 			err = -EPERM;
@@ -2591,6 +2592,21 @@
 	return status;
 }
  
+struct rpc_clnt *
+nfs4_proc_lookup_mountpoint(struct inode *dir, struct qstr *name,
+			    struct nfs_fh *fhandle, struct nfs_fattr *fattr)
+{
+	int status;
+	struct rpc_clnt *client = rpc_clone_client(NFS_CLIENT(dir));
+
+	status = nfs4_proc_lookup_common(&client, dir, name, fhandle, fattr);
+	if (status < 0) {
+		rpc_shutdown_client(client);
+		return ERR_PTR(status);
+	}
+	return client;
+}
+
 static int _nfs4_proc_access(struct inode *inode, struct nfs_access_entry *entry)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
@@ -4951,8 +4967,10 @@
 	fattr->nlink = 2;
 }
  
-static int _nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
-		struct nfs4_fs_locations *fs_locations, struct page *page)
+static int _nfs4_proc_fs_locations(struct rpc_clnt *client, struct inode *dir,
+				   const struct qstr *name,
+				   struct nfs4_fs_locations *fs_locations,
+				   struct page *page)
 {
 	struct nfs_server *server = NFS_SERVER(dir);
 	u32 bitmask[2] = {
  
  
@@ -4986,19 +5004,21 @@
 	nfs_fattr_init(&fs_locations->fattr);
 	fs_locations->server = server;
 	fs_locations->nlocations = 0;
-	status = nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
+	status = nfs4_call_sync(client, server, &msg, &args.seq_args, &res.seq_res, 0);
 	dprintk("%s: returned status = %d\n", __func__, status);
 	return status;
 }
  
-int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
-		struct nfs4_fs_locations *fs_locations, struct page *page)
+int nfs4_proc_fs_locations(struct rpc_clnt *client, struct inode *dir,
+			   const struct qstr *name,
+			   struct nfs4_fs_locations *fs_locations,
+			   struct page *page)
 {
 	struct nfs4_exception exception = { };
 	int err;
 	do {
 		err = nfs4_handle_exception(NFS_SERVER(dir),
-				_nfs4_proc_fs_locations(dir, name, fs_locations, page),
+				_nfs4_proc_fs_locations(client, dir, name, fs_locations, page),
 				&exception);
 	} while (exception.retry);
 	return err;
...	...	@@ -186,10 +186,10 @@
186	186
187	187	/* nfs4namespace.c */
188	188	#ifdef CONFIG_NFS_V4
189		-extern struct vfsmount nfs_do_refmount(struct dentry dentry);
	189	+extern struct vfsmount nfs_do_refmount(struct rpc_clnt client, struct dentry *dentry);
190	190	#else
191	191	static inline
192		-struct vfsmount nfs_do_refmount(struct dentry dentry)
	192	+struct vfsmount nfs_do_refmount(struct rpc_clnt client, struct dentry *dentry)
193	193	{
194	194	return ERR_PTR(-ENOENT);
195	195	}
...	...	@@ -200,6 +200,22 @@
200	200	out:
201	201	return err;
202	202	}
	203	+
	204	+static struct rpc_clnt nfs_lookup_mountpoint(struct inode dir,
	205	+ struct qstr *name,
	206	+ struct nfs_fh *fh,
	207	+ struct nfs_fattr *fattr)
	208	+{
	209	+ int err;
	210	+
	211	+ if (NFS_PROTO(dir)->version == 4)
	212	+ return nfs4_proc_lookup_mountpoint(dir, name, fh, fattr);
	213	+
	214	+ err = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, name, fh, fattr);
	215	+ if (err)
	216	+ return ERR_PTR(err);
	217	+ return rpc_clone_client(NFS_SERVER(dir)->client);
	218	+}
203	219	#else /* CONFIG_NFS_V4 */
204	220	static inline int nfs_lookup_with_sec(struct nfs_server *server,
205	221	struct dentry parent, struct dentry dentry,
...	...	@@ -209,6 +225,17 @@
209	225	{
210	226	return -EPERM;
211	227	}
	228	+
	229	+static inline struct rpc_clnt nfs_lookup_mountpoint(struct inode dir,
	230	+ struct qstr *name,
	231	+ struct nfs_fh *fh,
	232	+ struct nfs_fattr *fattr)
	233	+{
	234	+ int err = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, name, fh, fattr);
	235	+ if (err)
	236	+ return ERR_PTR(err);
	237	+ return rpc_clone_client(NFS_SERVER(dir)->client);
	238	+}
212	239	#endif /* CONFIG_NFS_V4 */
213	240
214	241	/*
215	242
...	...	@@ -226,11 +253,10 @@
226	253	struct vfsmount nfs_d_automount(struct path path)
227	254	{
228	255	struct vfsmount *mnt;
229		- struct nfs_server *server = NFS_SERVER(path->dentry->d_inode);
230	256	struct dentry *parent;
231	257	struct nfs_fh *fh = NULL;
232	258	struct nfs_fattr *fattr = NULL;
233		- int err;
	259	+ struct rpc_clnt *client;
234	260	rpc_authflavor_t flavor = RPC_AUTH_UNIX;
235	261
236	262	dprintk("--> nfs_d_automount()\n");
237	263
238	264
239	265
...	...	@@ -249,21 +275,19 @@
249	275
250	276	/* Look it up again to get its attributes */
251	277	parent = dget_parent(path->dentry);
252		- err = server->nfs_client->rpc_ops->lookup(server->client, parent->d_inode,
253		- &path->dentry->d_name,
254		- fh, fattr);
255		- if (err == -EPERM && NFS_PROTO(parent->d_inode)->secinfo != NULL)
256		- err = nfs_lookup_with_sec(server, parent, path->dentry, path, fh, fattr, &flavor);
	278	+ client = nfs_lookup_mountpoint(parent->d_inode, &path->dentry->d_name, fh, fattr);
257	279	dput(parent);
258		- if (err != 0) {
259		- mnt = ERR_PTR(err);
	280	+ if (IS_ERR(client)) {
	281	+ mnt = ERR_CAST(client);
260	282	goto out;
261	283	}
262	284
263	285	if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
264		- mnt = nfs_do_refmount(path->dentry);
	286	+ mnt = nfs_do_refmount(client, path->dentry);
265	287	else
266	288	mnt = nfs_do_submount(path->dentry, fh, fattr, flavor);
	289	+ rpc_shutdown_client(client);
	290	+
267	291	if (IS_ERR(mnt))
268	292	goto out;
269	293
...	...	@@ -216,8 +216,10 @@
216	216	extern int nfs41_init_clientid(struct nfs_client , struct rpc_cred );
217	217	extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait, bool roc);
218	218	extern int nfs4_server_capabilities(struct nfs_server server, struct nfs_fh fhandle);
219		-extern int nfs4_proc_fs_locations(struct inode dir, const struct qstr name,
220		- struct nfs4_fs_locations fs_locations, struct page page);
	219	+extern int nfs4_proc_fs_locations(struct rpc_clnt , struct inode , const struct qstr *,
	220	+ struct nfs4_fs_locations , struct page );
	221	+extern struct rpc_clnt nfs4_proc_lookup_mountpoint(struct inode , struct qstr *,
	222	+ struct nfs_fh , struct nfs_fattr );
221	223	extern int nfs4_proc_secinfo(struct inode , const struct qstr , struct nfs4_secinfo_flavors *);
222	224	extern int nfs4_release_lockowner(struct nfs4_lock_state *);
223	225	extern const struct xattr_handler *nfs4_xattr_handlers[];
...	...	@@ -300,7 +300,7 @@
300	300	* @dentry - dentry of referral
301	301	*
302	302	*/
303		-struct vfsmount nfs_do_refmount(struct dentry dentry)
	303	+struct vfsmount nfs_do_refmount(struct rpc_clnt client, struct dentry *dentry)
304	304	{
305	305	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
306	306	struct dentry *parent;
...	...	@@ -326,7 +326,7 @@
326	326	dprintk("%s: getting locations for %s/%s\n",
327	327	__func__, parent->d_name.name, dentry->d_name.name);
328	328
329		- err = nfs4_proc_fs_locations(parent->d_inode, &dentry->d_name, fs_locations, page);
	329	+ err = nfs4_proc_fs_locations(client, parent->d_inode, &dentry->d_name, fs_locations, page);
330	330	dput(parent);
331	331	if (err != 0 \|\|
332	332	fs_locations->nlocations <= 0 \|\|
...	...	@@ -2377,8 +2377,9 @@
2377	2377	* Note that we'll actually follow the referral later when
2378	2378	* we detect fsid mismatch in inode revalidation
2379	2379	*/
2380		-static int nfs4_get_referral(struct inode dir, const struct qstr name,
2381		- struct nfs_fattr fattr, struct nfs_fh fhandle)
	2380	+static int nfs4_get_referral(struct rpc_clnt client, struct inode dir,
	2381	+ const struct qstr name, struct nfs_fattr fattr,
	2382	+ struct nfs_fh *fhandle)
2382	2383	{
2383	2384	int status = -ENOMEM;
2384	2385	struct page *page = NULL;
...	...	@@ -2391,7 +2392,7 @@
2391	2392	if (locations == NULL)
2392	2393	goto out;
2393	2394
2394		- status = nfs4_proc_fs_locations(dir, name, locations, page);
	2395	+ status = nfs4_proc_fs_locations(client, dir, name, locations, page);
2395	2396	if (status != 0)
2396	2397	goto out;
2397	2398	/* Make sure server returned a different fsid for the referral */
...	...	@@ -2550,7 +2551,7 @@
2550	2551	err = -ENOENT;
2551	2552	goto out;
2552	2553	case -NFS4ERR_MOVED:
2553		- err = nfs4_get_referral(dir, name, fattr, fhandle);
	2554	+ err = nfs4_get_referral(client, dir, name, fattr, fhandle);
2554	2555	goto out;
2555	2556	case -NFS4ERR_WRONGSEC:
2556	2557	err = -EPERM;
...	...	@@ -2591,6 +2592,21 @@
2591	2592	return status;
2592	2593	}
2593	2594
	2595	+struct rpc_clnt *
	2596	+nfs4_proc_lookup_mountpoint(struct inode dir, struct qstr name,
	2597	+ struct nfs_fh fhandle, struct nfs_fattr fattr)
	2598	+{
	2599	+ int status;
	2600	+ struct rpc_clnt *client = rpc_clone_client(NFS_CLIENT(dir));
	2601	+
	2602	+ status = nfs4_proc_lookup_common(&client, dir, name, fhandle, fattr);
	2603	+ if (status < 0) {
	2604	+ rpc_shutdown_client(client);
	2605	+ return ERR_PTR(status);
	2606	+ }
	2607	+ return client;
	2608	+}
	2609	+
2594	2610	static int _nfs4_proc_access(struct inode inode, struct nfs_access_entry entry)
2595	2611	{
2596	2612	struct nfs_server *server = NFS_SERVER(inode);
...	...	@@ -4951,8 +4967,10 @@
4951	4967	fattr->nlink = 2;
4952	4968	}
4953	4969
4954		-static int _nfs4_proc_fs_locations(struct inode dir, const struct qstr name,
4955		- struct nfs4_fs_locations fs_locations, struct page page)
	4970	+static int _nfs4_proc_fs_locations(struct rpc_clnt client, struct inode dir,
	4971	+ const struct qstr *name,
	4972	+ struct nfs4_fs_locations *fs_locations,
	4973	+ struct page *page)
4956	4974	{
4957	4975	struct nfs_server *server = NFS_SERVER(dir);
4958	4976	u32 bitmask[2] = {
4959	4977
4960	4978
...	...	@@ -4986,19 +5004,21 @@
4986	5004	nfs_fattr_init(&fs_locations->fattr);
4987	5005	fs_locations->server = server;
4988	5006	fs_locations->nlocations = 0;
4989		- status = nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
	5007	+ status = nfs4_call_sync(client, server, &msg, &args.seq_args, &res.seq_res, 0);
4990	5008	dprintk("%s: returned status = %d\n", __func__, status);
4991	5009	return status;
4992	5010	}
4993	5011
4994		-int nfs4_proc_fs_locations(struct inode dir, const struct qstr name,
4995		- struct nfs4_fs_locations fs_locations, struct page page)
	5012	+int nfs4_proc_fs_locations(struct rpc_clnt client, struct inode dir,
	5013	+ const struct qstr *name,
	5014	+ struct nfs4_fs_locations *fs_locations,
	5015	+ struct page *page)
4996	5016	{
4997	5017	struct nfs4_exception exception = { };
4998	5018	int err;
4999	5019	do {
5000	5020	err = nfs4_handle_exception(NFS_SERVER(dir),
5001		- _nfs4_proc_fs_locations(dir, name, fs_locations, page),
	5021	+ _nfs4_proc_fs_locations(client, dir, name, fs_locations, page),
5002	5022	&exception);
5003	5023	} while (exception.retry);
5004	5024	return err;