From 13a791b4e63eb0537a7f804a340d6527485983b4 Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Mon, 13 Apr 2009 15:29:27 -0500 Subject: [PATCH] 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/crypto.c | 21 ++------------------- fs/ecryptfs/inode.c | 9 +++++++-- fs/ecryptfs/mmap.c | 11 +++++++++++ fs/ecryptfs/read_write.c | 32 +++++++++++++++++++++----------- 4 files changed, 41 insertions(+), 32 deletions(-) diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 8b65f289ee0..b91851f1cda 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -483,15 +483,7 @@ int ecryptfs_encrypt_page(struct page *page) ecryptfs_inode = page->mapping->host; crypt_stat = &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat); - if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { - rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page, - 0, PAGE_CACHE_SIZE); - if (rc) - printk(KERN_ERR "%s: Error attempting to copy " - "page at index [%ld]\n", __func__, - page->index); - goto out; - } + BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); enc_extent_page = alloc_page(GFP_USER); if (!enc_extent_page) { rc = -ENOMEM; @@ -620,16 +612,7 @@ int ecryptfs_decrypt_page(struct page *page) ecryptfs_inode = page->mapping->host; crypt_stat = &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat); - if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { - rc = ecryptfs_read_lower_page_segment(page, page->index, 0, - PAGE_CACHE_SIZE, - ecryptfs_inode); - if (rc) - printk(KERN_ERR "%s: Error attempting to copy " - "page at index [%ld]\n", __func__, - page->index); - goto out; - } + BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); enc_extent_page = alloc_page(GFP_USER); if (!enc_extent_page) { rc = -ENOMEM; diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 55b3145b807..5ed86e25b8a 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -814,6 +814,13 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) size_t num_zeros = (PAGE_CACHE_SIZE - (new_length & ~PAGE_CACHE_MASK)); + if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { + rc = vmtruncate(inode, new_length); + if (rc) + goto out_free; + rc = vmtruncate(lower_dentry->d_inode, new_length); + goto out_free; + } if (num_zeros) { char *zeros_virt; @@ -915,8 +922,6 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) } rc = 0; crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED); - mutex_unlock(&crypt_stat->cs_mutex); - goto out; } } mutex_unlock(&crypt_stat->cs_mutex); diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 46cec2b6979..5c6bab9786e 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -449,6 +449,7 @@ int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode) struct ecryptfs_crypt_stat *crypt_stat; crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; + BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) return ecryptfs_write_inode_size_to_xattr(ecryptfs_inode); else @@ -490,6 +491,16 @@ static int ecryptfs_write_end(struct file *file, ecryptfs_printk(KERN_DEBUG, "Not a new file\n"); ecryptfs_printk(KERN_DEBUG, "Calling fill_zeros_to_end_of_page" "(page w/ index = [0x%.16x], to = [%d])\n", index, to); + if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { + rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page, 0, + to); + if (!rc) { + rc = copied; + fsstack_copy_inode_size(ecryptfs_inode, + ecryptfs_inode_to_lower(ecryptfs_inode)); + } + goto out; + } /* Fills in zeros if 'to' goes beyond inode size */ rc = fill_zeros_to_end_of_page(page, to); if (rc) { diff --git a/fs/ecryptfs/read_write.c b/fs/ecryptfs/read_write.c index 75c2ea9fee3..a137c6ea2fe 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: -- 2.39.3