From 13a791b4e63eb0537a7f804a340d6527485983b4 Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Mon, 13 Apr 2009 15:29:27 -0500 Subject: eCryptfs: Fix data corruption when using ecryptfs_passthrough ecryptfs_passthrough is a mount option that allows eCryptfs to allow data to be written to non-eCryptfs files in the lower filesystem. The passthrough option was causing data corruption due to it not always being treated as a non-eCryptfs file. The first 8 bytes of an eCryptfs file contains the decrypted file size. This value was being written to the non-eCryptfs files, too. Also, extra 0x00 characters were being written to make the file size a multiple of PAGE_CACHE_SIZE. Signed-off-by: Tyler Hicks --- fs/ecryptfs/read_write.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) (limited to 'fs/ecryptfs/read_write.c') diff --git a/fs/ecryptfs/read_write.c b/fs/ecryptfs/read_write.c index 75c2ea9..a137c6e 100644 --- a/fs/ecryptfs/read_write.c +++ b/fs/ecryptfs/read_write.c @@ -117,13 +117,15 @@ int ecryptfs_write(struct file *ecryptfs_file, char *data, loff_t offset, size_t size) { struct page *ecryptfs_page; + struct ecryptfs_crypt_stat *crypt_stat; + struct inode *ecryptfs_inode = ecryptfs_file->f_dentry->d_inode; char *ecryptfs_page_virt; - loff_t ecryptfs_file_size = - i_size_read(ecryptfs_file->f_dentry->d_inode); + loff_t ecryptfs_file_size = i_size_read(ecryptfs_inode); loff_t data_offset = 0; loff_t pos; int rc = 0; + crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; /* * if we are writing beyond current size, then start pos * at the current size - we'll fill in zeros from there. @@ -184,7 +186,13 @@ int ecryptfs_write(struct file *ecryptfs_file, char *data, loff_t offset, flush_dcache_page(ecryptfs_page); SetPageUptodate(ecryptfs_page); unlock_page(ecryptfs_page); - rc = ecryptfs_encrypt_page(ecryptfs_page); + if (crypt_stat->flags & ECRYPTFS_ENCRYPTED) + rc = ecryptfs_encrypt_page(ecryptfs_page); + else + rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, + ecryptfs_page, + start_offset_in_page, + data_offset); page_cache_release(ecryptfs_page); if (rc) { printk(KERN_ERR "%s: Error encrypting " @@ -194,14 +202,16 @@ int ecryptfs_write(struct file *ecryptfs_file, char *data, loff_t offset, pos += num_bytes; } if ((offset + size) > ecryptfs_file_size) { - i_size_write(ecryptfs_file->f_dentry->d_inode, (offset + size)); - rc = ecryptfs_write_inode_size_to_metadata( - ecryptfs_file->f_dentry->d_inode); - if (rc) { - printk(KERN_ERR "Problem with " - "ecryptfs_write_inode_size_to_metadata; " - "rc = [%d]\n", rc); - goto out; + i_size_write(ecryptfs_inode, (offset + size)); + if (crypt_stat->flags & ECRYPTFS_ENCRYPTED) { + rc = ecryptfs_write_inode_size_to_metadata( + ecryptfs_inode); + if (rc) { + printk(KERN_ERR "Problem with " + "ecryptfs_write_inode_size_to_metadata; " + "rc = [%d]\n", rc); + goto out; + } } } out: -- cgit v1.1