Merge commit 'origin' into devel

4 files changed, 71 insertions, 4 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index ae04892a5e5..6cea7479c5b 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -710,6 +710,8 @@ int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
 
+	if (test_bit(NFS_INO_MOUNTPOINT, &NFS_I(inode)->flags))
+		return 0;
 	if (nd != NULL) {
 		/* VFS wants an on-the-wire revalidation */
 		if (nd->flags & LOOKUP_REVAL)
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 36cb99985d2..c49f6d8b42d 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -299,6 +299,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
 				else
 					inode->i_op = &nfs_mountpoint_inode_operations;
 				inode->i_fop = NULL;
+				set_bit(NFS_INO_MOUNTPOINT, &nfsi->flags);
 			}
 		} else if (S_ISLNK(inode->i_mode))
 			inode->i_op = &nfs_symlink_inode_operations;
@@ -1007,8 +1008,9 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 
 	server = NFS_SERVER(inode);
 	/* Update the fsid? */
-	if (S_ISDIR(inode->i_mode)
-			&& !nfs_fsid_equal(&server->fsid, &fattr->fsid))
+	if (S_ISDIR(inode->i_mode) &&
+			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
+			!test_bit(NFS_INO_MOUNTPOINT, &nfsi->flags))
 		server->fsid = fattr->fsid;
 
 	/*
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 985dc293103..4c1122a1384 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -3,6 +3,7 @@
  */
 
 #include <linux/mount.h>
+#include <linux/security.h>
 
 struct nfs_string;
 
@@ -57,6 +58,8 @@ struct nfs_parsed_mount_data {
 		char			*export_path;
 		int			protocol;
 	} nfs_server;
+
+	struct security_mnt_opts lsm_opts;
 };
 
 /* client.c */
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 1fb38184365..fcf4b982c88 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -684,8 +684,9 @@ static void nfs_parse_server_address(char *value,
 static int nfs_parse_mount_options(char *raw,
 				   struct nfs_parsed_mount_data *mnt)
 {
-	char *p, *string;
+	char *p, *string, *secdata;
 	unsigned short port = 0;
+	int rc;
 
 	if (!raw) {
 		dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
@@ -693,6 +694,20 @@ static int nfs_parse_mount_options(char *raw,
 	}
 	dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 
+	secdata = alloc_secdata();
+	if (!secdata)
+		goto out_nomem;
+
+	rc = security_sb_copy_data(raw, secdata);
+	if (rc)
+		goto out_security_failure;
+
+	rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
+	if (rc)
+		goto out_security_failure;
+
+	free_secdata(secdata);
+
 	while ((p = strsep(&raw, ",")) != NULL) {
 		substring_t args[MAX_OPT_ARGS];
 		int option, token;
@@ -1042,7 +1057,10 @@ static int nfs_parse_mount_options(char *raw,
 out_nomem:
 	printk(KERN_INFO "NFS: not enough memory to parse option\n");
 	return 0;
-
+out_security_failure:
+	free_secdata(secdata);
+	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
+	return 0;
 out_unrec_vers:
 	printk(KERN_INFO "NFS: unrecognized NFS version number\n");
 	return 0;
@@ -1214,6 +1232,33 @@ static int nfs_validate_mount_data(void *options,
 		args->namlen		= data->namlen;
 		args->bsize		= data->bsize;
 		args->auth_flavors[0]	= data->pseudoflavor;
+
+		/*
+		 * The legacy version 6 binary mount data from userspace has a
+		 * field used only to transport selinux information into the
+		 * the kernel.  To continue to support that functionality we
+		 * have a touch of selinux knowledge here in the NFS code. The
+		 * userspace code converted context=blah to just blah so we are
+		 * converting back to the full string selinux understands.
+		 */
+		if (data->context[0]){
+#ifdef CONFIG_SECURITY_SELINUX
+			int rc;
+			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
+			if (!opts_str)
+				return -ENOMEM;
+			strcpy(opts_str, "context=");
+			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
+			strcat(opts_str, &data->context[0]);
+			rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
+			kfree(opts_str);
+			if (rc)
+				return rc;
+#else
+			return -EINVAL;
+#endif
+		}
+
 		break;
 	default: {
 		unsigned int len;
@@ -1476,6 +1521,8 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 	};
 	int error;
 
+	security_init_mnt_opts(&data.lsm_opts);
+
 	/* Validate the mount data */
 	error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
 	if (error < 0)
@@ -1515,6 +1562,10 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 		goto error_splat_super;
 	}
 
+	error = security_sb_set_mnt_opts(s, &data.lsm_opts);
+	if (error)
+		goto error_splat_root;
+
 	s->s_flags |= MS_ACTIVE;
 	mnt->mnt_sb = s;
 	mnt->mnt_root = mntroot;
@@ -1523,12 +1574,15 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 out:
 	kfree(data.nfs_server.hostname);
 	kfree(data.mount_server.hostname);
+	security_free_mnt_opts(&data.lsm_opts);
 	return error;
 
 out_err_nosb:
 	nfs_free_server(server);
 	goto out;
 
+error_splat_root:
+	dput(mntroot);
 error_splat_super:
 	up_write(&s->s_umount);
 	deactivate_super(s);
@@ -1608,6 +1662,9 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
 	mnt->mnt_sb = s;
 	mnt->mnt_root = mntroot;
 
+	/* clone any lsm security options from the parent to the new sb */
+	security_sb_clone_mnt_opts(data->sb, s);
+
 	dprintk("<-- nfs_xdev_get_sb() = 0\n");
 	return 0;
 
@@ -1850,6 +1907,8 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
 	};
 	int error;
 
+	security_init_mnt_opts(&data.lsm_opts);
+
 	/* Validate the mount data */
 	error = nfs4_validate_mount_data(raw_data, &data, dev_name);
 	if (error < 0)
@@ -1898,6 +1957,7 @@ out:
 	kfree(data.client_address);
 	kfree(data.nfs_server.export_path);
 	kfree(data.nfs_server.hostname);
+	security_free_mnt_opts(&data.lsm_opts);
 	return error;
 
 out_free: