ecryptfs: discard ecryptfsd registration messages in miscdev

[linux-2.6-block.git] / fs / ecryptfs / file.c

diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index 24749bf0668f0c8d82a887e2b857c347a86a40f5..f0be29051528024d375057cfb6f39fc43568878b 100644 (file)
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -192,6 +192,13 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
                                      | ECRYPTFS_ENCRYPTED);
        }
        mutex_unlock(&crypt_stat->cs_mutex);
+       if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_RDONLY)
+           && !(file->f_flags & O_RDONLY)) {
+               rc = -EPERM;
+               printk(KERN_WARNING "%s: Lower persistent file is RO; eCryptfs "
+                      "file must hence be opened RO\n", __func__);
+               goto out;
+       }
        ecryptfs_set_file_lower(
                file, ecryptfs_inode_to_private(inode)->lower_file);
        if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {