From caeeeecfdaeada2998eb3c29c3ebd59afb79ef06 Mon Sep 17 00:00:00 2001 From: Michael Halcrow Date: Tue, 8 Jan 2008 15:33:02 -0800 Subject: [PATCH] eCryptfs: fix dentry handling on create error, unlink, and inode destroy This patch corrects some erroneous dentry handling in eCryptfs. If there is a problem creating the lower file, then there is nothing that the persistent lower file can do to really help us. This patch makes a vfs_create() failure in the lower filesystem always lead to an unconditional do_create failure in eCryptfs. Under certain sequences of operations, the eCryptfs dentry can remain in the dcache after an unlink. This patch calls d_drop() on the eCryptfs dentry to correct this. eCryptfs has no business calling d_delete() directly on a lower filesystem's dentry. This patch removes the call to d_delete() on the lower persistent file's dentry in ecryptfs_destroy_inode(). (Thanks to David Kleikamp, Eric Sandeen, and Jeff Moyer for helping identify and resolve this issue) Signed-off-by: Michael Halcrow Cc: Dave Kleikamp Cc: Eric Sandeen Cc: Jeff Moyer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ecryptfs/inode.c | 20 ++++---------------- fs/ecryptfs/super.c | 1 - 2 files changed, 4 insertions(+), 17 deletions(-) diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 0b1ab016fa2e..5a719180983c 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -120,22 +120,9 @@ ecryptfs_do_create(struct inode *directory_inode, rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, ecryptfs_dentry, mode, nd); if (rc) { - struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode; - struct ecryptfs_inode_info *inode_info = - ecryptfs_inode_to_private(ecryptfs_inode); - - printk(KERN_WARNING "%s: Error creating underlying file; " - "rc = [%d]; checking for existing\n", __FUNCTION__, rc); - if (inode_info) { - mutex_lock(&inode_info->lower_file_mutex); - if (!inode_info->lower_file) { - mutex_unlock(&inode_info->lower_file_mutex); - printk(KERN_ERR "%s: Failure to set underlying " - "file; rc = [%d]\n", __FUNCTION__, rc); - goto out_lock; - } - mutex_unlock(&inode_info->lower_file_mutex); - } + printk(KERN_ERR "%s: Failure to create dentry in lower fs; " + "rc = [%d]\n", __FUNCTION__, rc); + goto out_lock; } rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, directory_inode->i_sb, 0); @@ -451,6 +438,7 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) dentry->d_inode->i_nlink = ecryptfs_inode_to_lower(dentry->d_inode)->i_nlink; dentry->d_inode->i_ctime = dir->i_ctime; + d_drop(dentry); out_unlock: unlock_parent(lower_dentry); return rc; diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c index f8cdab2bee3d..4859c4eecd65 100644 --- a/fs/ecryptfs/super.c +++ b/fs/ecryptfs/super.c @@ -86,7 +86,6 @@ static void ecryptfs_destroy_inode(struct inode *inode) fput(inode_info->lower_file); inode_info->lower_file = NULL; d_drop(lower_dentry); - d_delete(lower_dentry); } } mutex_unlock(&inode_info->lower_file_mutex);