1 files changed, 77 insertions, 22 deletions

diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index f3ece8ed3203..2f336ace7555 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -32,9 +32,9 @@ int nfs_mountpoint_expiry_timeout = 500 * HZ;
 /*
  * nfs_path - reconstruct the path given an arbitrary dentry
  * @base - used to return pointer to the end of devname part of path
- * @dentry - pointer to dentry
+ * @dentry_in - pointer to dentry
  * @buffer - result buffer
- * @buflen - length of buffer
+ * @buflen_in - length of buffer
  * @flags - options (see below)
  *
  * Helper function for constructing the server pathname
@@ -49,15 +49,19 @@ int nfs_mountpoint_expiry_timeout = 500 * HZ;
  *		       the original device (export) name
  *		       (if unset, the original name is returned verbatim)
  */
-char *nfs_path(char **p, struct dentry *dentry, char *buffer, ssize_t buflen,
-	       unsigned flags)
+char *nfs_path(char **p, struct dentry *dentry_in, char *buffer,
+	       ssize_t buflen_in, unsigned flags)
 {
 	char *end;
 	int namelen;
 	unsigned seq;
 	const char *base;
+	struct dentry *dentry;
+	ssize_t buflen;
 
 rename_retry:
+	buflen = buflen_in;
+	dentry = dentry_in;
 	end = buffer+buflen;
 	*--end = '\0';
 	buflen--;
@@ -145,6 +149,7 @@ struct vfsmount *nfs_d_automount(struct path *path)
 	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
 	struct nfs_server *server = NFS_SERVER(d_inode(path->dentry));
 	struct nfs_client *client = server->nfs_client;
+	int timeout = READ_ONCE(nfs_mountpoint_expiry_timeout);
 	int ret;
 
 	if (IS_ROOT(path->dentry))
@@ -170,7 +175,7 @@ struct vfsmount *nfs_d_automount(struct path *path)
 	}
 
 	/* for submounts we want the same server; referrals will reassign */
-	memcpy(&ctx->nfs_server.address, &client->cl_addr, client->cl_addrlen);
+	memcpy(&ctx->nfs_server._address, &client->cl_addr, client->cl_addrlen);
 	ctx->nfs_server.addrlen	= client->cl_addrlen;
 	ctx->nfs_server.port	= server->port;
 
@@ -190,12 +195,12 @@ struct vfsmount *nfs_d_automount(struct path *path)
 	if (IS_ERR(mnt))
 		goto out_fc;
 
-	if (nfs_mountpoint_expiry_timeout < 0)
+	mntget(mnt); /* prevent immediate expiration */
+	if (timeout <= 0)
 		goto out_fc;
 
-	mntget(mnt); /* prevent immediate expiration */
 	mnt_set_expiry(mnt, &nfs_automount_list);
-	schedule_delayed_work(&nfs_automount_task, nfs_mountpoint_expiry_timeout);
+	schedule_delayed_work(&nfs_automount_task, timeout);
 
 out_fc:
 	put_fs_context(fc);
@@ -203,20 +208,23 @@ out_fc:
 }
 
 static int
-nfs_namespace_getattr(const struct path *path, struct kstat *stat,
-			u32 request_mask, unsigned int query_flags)
+nfs_namespace_getattr(struct user_namespace *mnt_userns,
+		      const struct path *path, struct kstat *stat,
+		      u32 request_mask, unsigned int query_flags)
 {
 	if (NFS_FH(d_inode(path->dentry))->size != 0)
-		return nfs_getattr(path, stat, request_mask, query_flags);
-	generic_fillattr(d_inode(path->dentry), stat);
+		return nfs_getattr(mnt_userns, path, stat, request_mask,
+				   query_flags);
+	generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
 	return 0;
 }
 
 static int
-nfs_namespace_setattr(struct dentry *dentry, struct iattr *attr)
+nfs_namespace_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		      struct iattr *attr)
 {
 	if (NFS_FH(d_inode(dentry))->size != 0)
-		return nfs_setattr(dentry, attr);
+		return nfs_setattr(mnt_userns, dentry, attr);
 	return -EACCES;
 }
 
@@ -233,10 +241,11 @@ const struct inode_operations nfs_referral_inode_operations = {
 static void nfs_expire_automounts(struct work_struct *work)
 {
 	struct list_head *list = &nfs_automount_list;
+	int timeout = READ_ONCE(nfs_mountpoint_expiry_timeout);
 
 	mark_mounts_for_expiry(list);
-	if (!list_empty(list))
-		schedule_delayed_work(&nfs_automount_task, nfs_mountpoint_expiry_timeout);
+	if (!list_empty(list) && timeout > 0)
+		schedule_delayed_work(&nfs_automount_task, timeout);
 }
 
 void nfs_release_automount_timer(void)
@@ -247,10 +256,7 @@ void nfs_release_automount_timer(void)
 
 /**
  * nfs_do_submount - set up mountpoint when crossing a filesystem boundary
- * @dentry: parent directory
- * @fh: filehandle for new root dentry
- * @fattr: attributes for new root inode
- * @authflavor: security flavor to use when performing the mount
+ * @fc: pointer to struct nfs_fs_context
  *
  */
 int nfs_do_submount(struct fs_context *fc)
@@ -302,8 +308,7 @@ int nfs_submount(struct fs_context *fc, struct nfs_server *server)
 
 	/* Look it up again to get its attributes */
 	err = server->nfs_client->rpc_ops->lookup(d_inode(parent), dentry,
-						  ctx->mntfh, ctx->clone_data.fattr,
-						  NULL);
+						  ctx->mntfh, ctx->clone_data.fattr);
 	dput(parent);
 	if (err != 0)
 		return err;
@@ -312,3 +317,53 @@ int nfs_submount(struct fs_context *fc, struct nfs_server *server)
 	return nfs_do_submount(fc);
 }
 EXPORT_SYMBOL_GPL(nfs_submount);
+
+static int param_set_nfs_timeout(const char *val, const struct kernel_param *kp)
+{
+	long num;
+	int ret;
+
+	if (!val)
+		return -EINVAL;
+	ret = kstrtol(val, 0, &num);
+	if (ret)
+		return -EINVAL;
+	if (num > 0) {
+		if (num >= INT_MAX / HZ)
+			num = INT_MAX;
+		else
+			num *= HZ;
+		*((int *)kp->arg) = num;
+		if (!list_empty(&nfs_automount_list))
+			mod_delayed_work(system_wq, &nfs_automount_task, num);
+	} else {
+		*((int *)kp->arg) = -1*HZ;
+		cancel_delayed_work(&nfs_automount_task);
+	}
+	return 0;
+}
+
+static int param_get_nfs_timeout(char *buffer, const struct kernel_param *kp)
+{
+	long num = *((int *)kp->arg);
+
+	if (num > 0) {
+		if (num >= INT_MAX - (HZ - 1))
+			num = INT_MAX / HZ;
+		else
+			num = (num + (HZ - 1)) / HZ;
+	} else
+		num = -1;
+	return scnprintf(buffer, PAGE_SIZE, "%li\n", num);
+}
+
+static const struct kernel_param_ops param_ops_nfs_timeout = {
+	.set = param_set_nfs_timeout,
+	.get = param_get_nfs_timeout,
+};
+#define param_check_nfs_timeout(name, p) __param_check(name, p, int)
+
+module_param(nfs_mountpoint_expiry_timeout, nfs_timeout, 0644);
+MODULE_PARM_DESC(nfs_mountpoint_expiry_timeout,
+		"Set the NFS automounted mountpoint timeout value (seconds)."
+		"Values <= 0 turn expiration off.");