Commit ca8e34f2 authored by Tyler Hicks's avatar Tyler Hicks
Browse files

eCryptfs: Lock lower directory inode mutex during lookup 



This patch locks the lower directory inode's i_mutex before calling
lookup_one_len() to find the appropriate dentry in the lower filesystem.
This bug was found thanks to the warning set in commit 2f9092e1.

Signed-off-by: default avatarTyler Hicks <tyhicks@linux.vnet.ibm.com>
parent e77cc8d2

fs/ecryptfs/inode.c

+4 −0
Original line number Diff line number Diff line
@@ -379,9 +379,11 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, 
		goto out_d_drop;

	}

	lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);

	mutex_lock(&lower_dir_dentry->d_inode->i_mutex);

	lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,

				      lower_dir_dentry,

				      ecryptfs_dentry->d_name.len);

	mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);

	if (IS_ERR(lower_dentry)) {

		rc = PTR_ERR(lower_dentry);

		printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
@@ -406,9 +408,11 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, 
		       "filename; rc = [%d]\n", __func__, rc);

		goto out_d_drop;

	}

	mutex_lock(&lower_dir_dentry->d_inode->i_mutex);

	lower_dentry = lookup_one_len(encrypted_and_encoded_name,

				      lower_dir_dentry,

				      encrypted_and_encoded_name_size - 1);

	mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);

	if (IS_ERR(lower_dentry)) {

		rc = PTR_ERR(lower_dentry);

		printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "

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