diff options
| -rw-r--r-- | fs/ecryptfs/inode.c | 23 | ||||
| -rw-r--r-- | fs/ecryptfs/main.c | 65 | ||||
| -rw-r--r-- | fs/ecryptfs/super.c | 22 |
3 files changed, 103 insertions, 7 deletions
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 7192a810bbe6..c746b5d8a336 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -119,10 +119,23 @@ ecryptfs_do_create(struct inode *directory_inode, } rc = ecryptfs_create_underlying_file(lower_dir_dentry->d_inode, ecryptfs_dentry, mode, nd); - if (unlikely(rc)) { - ecryptfs_printk(KERN_ERR, - "Failure to create underlying file\n"); - goto out_lock; + 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); + } } rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, directory_inode->i_sb, 0); @@ -252,6 +265,8 @@ ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, { int rc; + /* ecryptfs_do_create() calls ecryptfs_interpose(), which opens + * the crypt_stat->lower_file (persistent file) */ rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); if (unlikely(rc)) { ecryptfs_printk(KERN_WARNING, "Failed to create file in" diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index 49545951912f..fb9d85b5c7b8 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -99,6 +99,64 @@ void __ecryptfs_printk(const char *fmt, ...) } /** + * ecryptfs_init_persistent_file + * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with + * the lower dentry and the lower mount set + * + * eCryptfs only ever keeps a single open file for every lower + * inode. All I/O operations to the lower inode occur through that + * file. When the first eCryptfs dentry that interposes with the first + * lower dentry for that inode is created, this function creates the + * persistent file struct and associates it with the eCryptfs + * inode. When the eCryptfs inode is destroyed, the file is closed. + * + * The persistent file will be opened with read/write permissions, if + * possible. Otherwise, it is opened read-only. + * + * This function does nothing if a lower persistent file is already + * associated with the eCryptfs inode. + * + * Returns zero on success; non-zero otherwise + */ +int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry) +{ + struct ecryptfs_inode_info *inode_info = + ecryptfs_inode_to_private(ecryptfs_dentry->d_inode); + int rc = 0; + + mutex_lock(&inode_info->lower_file_mutex); + if (!inode_info->lower_file) { + struct dentry *lower_dentry; + struct vfsmount *lower_mnt = + ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry); + + lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); + /* Corresponding dput() and mntput() are done when the + * persistent file is fput() when the eCryptfs inode + * is destroyed. */ + dget(lower_dentry); + mntget(lower_mnt); + inode_info->lower_file = dentry_open(lower_dentry, + lower_mnt, + (O_RDWR | O_LARGEFILE)); + if (IS_ERR(inode_info->lower_file)) + inode_info->lower_file = dentry_open(lower_dentry, + lower_mnt, + (O_RDONLY + | O_LARGEFILE)); + if (IS_ERR(inode_info->lower_file)) { + printk(KERN_ERR "Error opening lower persistent file " + "for lower_dentry [0x%p] and lower_mnt [0x%p]\n", + lower_dentry, lower_mnt); + rc = PTR_ERR(inode_info->lower_file); + inode_info->lower_file = NULL; + } + } + mutex_unlock(&inode_info->lower_file_mutex); + return rc; +} + +/** * ecryptfs_interpose * @lower_dentry: Existing dentry in the lower filesystem * @dentry: ecryptfs' dentry @@ -155,6 +213,13 @@ int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, /* This size will be overwritten for real files w/ headers and * other metadata */ fsstack_copy_inode_size(inode, lower_inode); + rc = ecryptfs_init_persistent_file(dentry); + if (rc) { + printk(KERN_ERR "%s: Error attempting to initialize the " + "persistent file for the dentry with name [%s]; " + "rc = [%d]\n", __FUNCTION__, dentry->d_name.name, rc); + goto out; + } out: return rc; } diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c index 18d77f8aa7cd..b97e2106f670 100644 --- a/fs/ecryptfs/super.c +++ b/fs/ecryptfs/super.c @@ -27,6 +27,7 @@ #include <linux/mount.h> #include <linux/key.h> #include <linux/seq_file.h> +#include <linux/file.h> #include <linux/crypto.h> #include "ecryptfs_kernel.h" @@ -63,9 +64,10 @@ out: * ecryptfs_destroy_inode * @inode: The ecryptfs inode * - * This is used during the final destruction of the inode. - * All allocation of memory related to the inode, including allocated - * memory in the crypt_stat struct, will be released here. + * This is used during the final destruction of the inode. All + * allocation of memory related to the inode, including allocated + * memory in the crypt_stat struct, will be released here. This + * function also fput()'s the persistent file for the lower inode. * There should be no chance that this deallocation will be missed. */ static void ecryptfs_destroy_inode(struct inode *inode) @@ -73,6 +75,20 @@ static void ecryptfs_destroy_inode(struct inode *inode) struct ecryptfs_inode_info *inode_info; inode_info = ecryptfs_inode_to_private(inode); + mutex_lock(&inode_info->lower_file_mutex); + if (inode_info->lower_file) { + struct dentry *lower_dentry = + inode_info->lower_file->f_dentry; + + BUG_ON(!lower_dentry); + if (lower_dentry->d_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); ecryptfs_destroy_crypt_stat(&inode_info->crypt_stat); kmem_cache_free(ecryptfs_inode_info_cache, inode_info); } |