diff options
Diffstat (limited to 'fs/ecryptfs/inode.c')
-rw-r--r-- | fs/ecryptfs/inode.c | 164 |
1 files changed, 112 insertions, 52 deletions
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 056fed62d0d..4a430ab4115 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -282,7 +282,8 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, goto out; } rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, - ecryptfs_dir_inode->i_sb, 1); + ecryptfs_dir_inode->i_sb, + ECRYPTFS_INTERPOSE_FLAG_D_ADD); if (rc) { printk(KERN_ERR "%s: Error interposing; rc = [%d]\n", __func__, rc); @@ -463,9 +464,6 @@ out_lock: unlock_dir(lower_dir_dentry); dput(lower_new_dentry); dput(lower_old_dentry); - d_drop(lower_old_dentry); - d_drop(new_dentry); - d_drop(old_dentry); return rc; } @@ -614,6 +612,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct dentry *lower_new_dentry; struct dentry *lower_old_dir_dentry; struct dentry *lower_new_dir_dentry; + struct dentry *trap = NULL; lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry); lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry); @@ -621,14 +620,24 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, dget(lower_new_dentry); lower_old_dir_dentry = dget_parent(lower_old_dentry); lower_new_dir_dentry = dget_parent(lower_new_dentry); - lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); + trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry); + /* source should not be ancestor of target */ + if (trap == lower_old_dentry) { + rc = -EINVAL; + goto out_lock; + } + /* target should not be ancestor of source */ + if (trap == lower_new_dentry) { + rc = -ENOTEMPTY; + goto out_lock; + } rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, lower_new_dir_dentry->d_inode, lower_new_dentry); if (rc) goto out_lock; - fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode, NULL); + fsstack_copy_attr_all(new_dir, lower_new_dir_dentry->d_inode); if (new_dir != old_dir) - fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode, NULL); + fsstack_copy_attr_all(old_dir, lower_old_dir_dentry->d_inode); out_lock: unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry); dput(lower_new_dentry->d_parent); @@ -715,31 +724,31 @@ static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) /* Released in ecryptfs_put_link(); only release here on error */ buf = kmalloc(len, GFP_KERNEL); if (!buf) { - rc = -ENOMEM; + buf = ERR_PTR(-ENOMEM); goto out; } old_fs = get_fs(); set_fs(get_ds()); rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); set_fs(old_fs); - if (rc < 0) - goto out_free; - else + if (rc < 0) { + kfree(buf); + buf = ERR_PTR(rc); + } else buf[rc] = '\0'; - rc = 0; - nd_set_link(nd, buf); - goto out; -out_free: - kfree(buf); out: - return ERR_PTR(rc); + nd_set_link(nd, buf); + return NULL; } static void ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr) { - /* Free the char* */ - kfree(nd_get_link(nd)); + char *buf = nd_get_link(nd); + if (!IS_ERR(buf)) { + /* Free the char* */ + kfree(buf); + } } /** @@ -772,18 +781,23 @@ upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, } /** - * ecryptfs_truncate + * truncate_upper * @dentry: The ecryptfs layer dentry - * @new_length: The length to expand the file to + * @ia: Address of the ecryptfs inode's attributes + * @lower_ia: Address of the lower inode's attributes * * Function to handle truncations modifying the size of the file. Note * that the file sizes are interpolated. When expanding, we are simply - * writing strings of 0's out. When truncating, we need to modify the - * underlying file size according to the page index interpolations. + * writing strings of 0's out. When truncating, we truncate the upper + * inode and update the lower_ia according to the page index + * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return, + * the caller must use lower_ia in a call to notify_change() to perform + * the truncation of the lower inode. * * Returns zero on success; non-zero otherwise */ -int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) +static int truncate_upper(struct dentry *dentry, struct iattr *ia, + struct iattr *lower_ia) { int rc = 0; struct inode *inode = dentry->d_inode; @@ -794,8 +808,10 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) loff_t lower_size_before_truncate; loff_t lower_size_after_truncate; - if (unlikely((new_length == i_size))) + if (unlikely((ia->ia_size == i_size))) { + lower_ia->ia_valid &= ~ATTR_SIZE; goto out; + } crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; /* Set up a fake ecryptfs file, this is used to interface with * the file in the underlying filesystem so that the @@ -815,28 +831,30 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) &fake_ecryptfs_file, ecryptfs_inode_to_private(dentry->d_inode)->lower_file); /* Switch on growing or shrinking file */ - if (new_length > i_size) { + if (ia->ia_size > i_size) { char zero[] = { 0x00 }; + lower_ia->ia_valid &= ~ATTR_SIZE; /* Write a single 0 at the last position of the file; * this triggers code that will fill in 0's throughout * the intermediate portion of the previous end of the * file and the new and of the file */ rc = ecryptfs_write(&fake_ecryptfs_file, zero, - (new_length - 1), 1); - } else { /* new_length < i_size_read(inode) */ - /* We're chopping off all the pages down do the page - * in which new_length is located. Fill in the end of - * that page from (new_length & ~PAGE_CACHE_MASK) to + (ia->ia_size - 1), 1); + } else { /* ia->ia_size < i_size_read(inode) */ + /* We're chopping off all the pages down to the page + * in which ia->ia_size is located. Fill in the end of + * that page from (ia->ia_size & ~PAGE_CACHE_MASK) to * PAGE_CACHE_SIZE with zeros. */ size_t num_zeros = (PAGE_CACHE_SIZE - - (new_length & ~PAGE_CACHE_MASK)); + - (ia->ia_size & ~PAGE_CACHE_MASK)); if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { - rc = vmtruncate(inode, new_length); + rc = vmtruncate(inode, ia->ia_size); if (rc) goto out_free; - rc = vmtruncate(lower_dentry->d_inode, new_length); + lower_ia->ia_size = ia->ia_size; + lower_ia->ia_valid |= ATTR_SIZE; goto out_free; } if (num_zeros) { @@ -848,7 +866,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) goto out_free; } rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt, - new_length, num_zeros); + ia->ia_size, num_zeros); kfree(zeros_virt); if (rc) { printk(KERN_ERR "Error attempting to zero out " @@ -857,7 +875,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) goto out_free; } } - vmtruncate(inode, new_length); + vmtruncate(inode, ia->ia_size); rc = ecryptfs_write_inode_size_to_metadata(inode); if (rc) { printk(KERN_ERR "Problem with " @@ -870,10 +888,12 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) lower_size_before_truncate = upper_size_to_lower_size(crypt_stat, i_size); lower_size_after_truncate = - upper_size_to_lower_size(crypt_stat, new_length); - if (lower_size_after_truncate < lower_size_before_truncate) - vmtruncate(lower_dentry->d_inode, - lower_size_after_truncate); + upper_size_to_lower_size(crypt_stat, ia->ia_size); + if (lower_size_after_truncate < lower_size_before_truncate) { + lower_ia->ia_size = lower_size_after_truncate; + lower_ia->ia_valid |= ATTR_SIZE; + } else + lower_ia->ia_valid &= ~ATTR_SIZE; } out_free: if (ecryptfs_file_to_private(&fake_ecryptfs_file)) @@ -883,6 +903,33 @@ out: return rc; } +/** + * ecryptfs_truncate + * @dentry: The ecryptfs layer dentry + * @new_length: The length to expand the file to + * + * Simple function that handles the truncation of an eCryptfs inode and + * its corresponding lower inode. + * + * Returns zero on success; non-zero otherwise + */ +int ecryptfs_truncate(struct dentry *dentry, loff_t new_length) +{ + struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length }; + struct iattr lower_ia = { .ia_valid = 0 }; + int rc; + + rc = truncate_upper(dentry, &ia, &lower_ia); + if (!rc && lower_ia.ia_valid & ATTR_SIZE) { + struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); + + mutex_lock(&lower_dentry->d_inode->i_mutex); + rc = notify_change(lower_dentry, &lower_ia); + mutex_unlock(&lower_dentry->d_inode->i_mutex); + } + return rc; +} + static int ecryptfs_permission(struct inode *inode, int mask) { @@ -905,6 +952,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) { int rc = 0; struct dentry *lower_dentry; + struct iattr lower_ia; struct inode *inode; struct inode *lower_inode; struct ecryptfs_crypt_stat *crypt_stat; @@ -943,15 +991,11 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) } } mutex_unlock(&crypt_stat->cs_mutex); + memcpy(&lower_ia, ia, sizeof(lower_ia)); + if (ia->ia_valid & ATTR_FILE) + lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file); if (ia->ia_valid & ATTR_SIZE) { - ecryptfs_printk(KERN_DEBUG, - "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n", - ia->ia_valid, ATTR_SIZE); - rc = ecryptfs_truncate(dentry, ia->ia_size); - /* ecryptfs_truncate handles resizing of the lower file */ - ia->ia_valid &= ~ATTR_SIZE; - ecryptfs_printk(KERN_DEBUG, "ia->ia_valid = [%x]\n", - ia->ia_valid); + rc = truncate_upper(dentry, ia, &lower_ia); if (rc < 0) goto out; } @@ -960,14 +1004,29 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia) * mode change is for clearing setuid/setgid bits. Allow lower fs * to interpret this in its own way. */ - if (ia->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) - ia->ia_valid &= ~ATTR_MODE; + if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID)) + lower_ia.ia_valid &= ~ATTR_MODE; mutex_lock(&lower_dentry->d_inode->i_mutex); - rc = notify_change(lower_dentry, ia); + rc = notify_change(lower_dentry, &lower_ia); mutex_unlock(&lower_dentry->d_inode->i_mutex); out: - fsstack_copy_attr_all(inode, lower_inode, NULL); + fsstack_copy_attr_all(inode, lower_inode); + return rc; +} + +int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat) +{ + struct kstat lower_stat; + int rc; + + rc = vfs_getattr(ecryptfs_dentry_to_lower_mnt(dentry), + ecryptfs_dentry_to_lower(dentry), &lower_stat); + if (!rc) { + generic_fillattr(dentry->d_inode, stat); + stat->blocks = lower_stat.blocks; + } return rc; } @@ -1100,6 +1159,7 @@ const struct inode_operations ecryptfs_dir_iops = { const struct inode_operations ecryptfs_main_iops = { .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, + .getattr = ecryptfs_getattr, .setxattr = ecryptfs_setxattr, .getxattr = ecryptfs_getxattr, .listxattr = ecryptfs_listxattr, |