X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fecryptfs%2Finode.c;h=65dee2f336aea15076958de5f60ea0f10280026d;hb=36e15263aa5dcf3b72f1f88437e69497782b7ab8;hp=89209f00f9c74ecc752ed944f26ecff6e2f5c974;hpb=f419a2e3b64def707e1384ee38abb77f99af5f6d;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 89209f0..65dee2f 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include "ecryptfs_kernel.h" @@ -52,8 +53,7 @@ static void unlock_dir(struct dentry *dir) /** * ecryptfs_create_underlying_file * @lower_dir_inode: inode of the parent in the lower fs of the new file - * @lower_dentry: New file's dentry in the lower fs - * @ecryptfs_dentry: New file's dentry in ecryptfs + * @dentry: New file's dentry * @mode: The mode of the new file * @nd: nameidata of ecryptfs' parent's dentry & vfsmount * @@ -142,19 +142,10 @@ out: static int grow_file(struct dentry *ecryptfs_dentry) { struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode; - struct file fake_file; - struct ecryptfs_file_info tmp_file_info; char zero_virt[] = { 0x00 }; int rc = 0; - memset(&fake_file, 0, sizeof(fake_file)); - fake_file.f_path.dentry = ecryptfs_dentry; - memset(&tmp_file_info, 0, sizeof(tmp_file_info)); - ecryptfs_set_file_private(&fake_file, &tmp_file_info); - ecryptfs_set_file_lower( - &fake_file, - ecryptfs_inode_to_private(ecryptfs_inode)->lower_file); - rc = ecryptfs_write(&fake_file, zero_virt, 0, 1); + rc = ecryptfs_write(ecryptfs_inode, zero_virt, 0, 1); i_size_write(ecryptfs_inode, 0); rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode); ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |= @@ -228,8 +219,7 @@ 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) */ + /* ecryptfs_do_create() calls ecryptfs_interpose() */ rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); if (unlikely(rc)) { ecryptfs_printk(KERN_WARNING, "Failed to create file in" @@ -244,158 +234,195 @@ out: } /** - * ecryptfs_lookup - * @dir: inode - * @dentry: The dentry - * @nd: nameidata, may be NULL - * - * Find a file on disk. If the file does not exist, then we'll add it to the - * dentry cache and continue on to read it from the disk. + * ecryptfs_lookup_and_interpose_lower - Perform a lookup */ -static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, - struct nameidata *nd) +int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, + struct dentry *lower_dentry, + struct inode *ecryptfs_dir_inode, + struct nameidata *ecryptfs_nd) { - int rc = 0; struct dentry *lower_dir_dentry; - struct dentry *lower_dentry; struct vfsmount *lower_mnt; - char *encoded_name; - int encoded_namelen; - struct ecryptfs_crypt_stat *crypt_stat = NULL; + struct inode *lower_inode; struct ecryptfs_mount_crypt_stat *mount_crypt_stat; + struct ecryptfs_crypt_stat *crypt_stat; char *page_virt = NULL; - struct inode *lower_inode; u64 file_size; + int rc = 0; - lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); - dentry->d_op = &ecryptfs_dops; - if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, ".")) - || (dentry->d_name.len == 2 - && !strcmp(dentry->d_name.name, ".."))) { - d_drop(dentry); - goto out; - } - encoded_namelen = ecryptfs_encode_filename(crypt_stat, - dentry->d_name.name, - dentry->d_name.len, - &encoded_name); - if (encoded_namelen < 0) { - rc = encoded_namelen; - d_drop(dentry); - goto out; - } - ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen " - "= [%d]\n", encoded_name, encoded_namelen); - lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry, - encoded_namelen - 1); - kfree(encoded_name); - if (IS_ERR(lower_dentry)) { - ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n"); - rc = PTR_ERR(lower_dentry); - d_drop(dentry); - goto out; - } - lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent)); - ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->" - "d_name.name = [%s]\n", lower_dentry, - lower_dentry->d_name.name); + lower_dir_dentry = lower_dentry->d_parent; + lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt( + ecryptfs_dentry->d_parent)); lower_inode = lower_dentry->d_inode; - fsstack_copy_attr_atime(dir, lower_dir_dentry->d_inode); + fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode); BUG_ON(!atomic_read(&lower_dentry->d_count)); - ecryptfs_set_dentry_private(dentry, + ecryptfs_set_dentry_private(ecryptfs_dentry, kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL)); - if (!ecryptfs_dentry_to_private(dentry)) { + if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) { rc = -ENOMEM; - ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting " - "to allocate ecryptfs_dentry_info struct\n"); + printk(KERN_ERR "%s: Out of memory whilst attempting " + "to allocate ecryptfs_dentry_info struct\n", + __func__); goto out_dput; } - ecryptfs_set_dentry_lower(dentry, lower_dentry); - ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt); + ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry); + ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt); if (!lower_dentry->d_inode) { /* We want to add because we couldn't find in lower */ - d_add(dentry, NULL); + d_add(ecryptfs_dentry, NULL); goto out; } - rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, + rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, + ecryptfs_dir_inode->i_sb, ECRYPTFS_INTERPOSE_FLAG_D_ADD); if (rc) { - ecryptfs_printk(KERN_ERR, "Error interposing\n"); + printk(KERN_ERR "%s: Error interposing; rc = [%d]\n", + __func__, rc); goto out; } - if (S_ISDIR(lower_inode->i_mode)) { - ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n"); + if (S_ISDIR(lower_inode->i_mode)) goto out; - } - if (S_ISLNK(lower_inode->i_mode)) { - ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n"); + if (S_ISLNK(lower_inode->i_mode)) goto out; - } - if (special_file(lower_inode->i_mode)) { - ecryptfs_printk(KERN_DEBUG, "Is a special file; returning\n"); + if (special_file(lower_inode->i_mode)) goto out; - } - if (!nd) { - ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave" - "as we *think* we are about to unlink\n"); + if (!ecryptfs_nd) goto out; - } /* Released in this function */ - page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, - GFP_USER); + page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER); if (!page_virt) { + printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n", + __func__); rc = -ENOMEM; - ecryptfs_printk(KERN_ERR, - "Cannot ecryptfs_kmalloc a page\n"); goto out; } - crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; - if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) - ecryptfs_set_default_sizes(crypt_stat); - if (!ecryptfs_inode_to_private(dentry->d_inode)->lower_file) { - rc = ecryptfs_init_persistent_file(dentry); + if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) { + rc = ecryptfs_init_persistent_file(ecryptfs_dentry); if (rc) { printk(KERN_ERR "%s: Error attempting to initialize " "the persistent file for the dentry with name " "[%s]; rc = [%d]\n", __func__, - dentry->d_name.name, rc); - goto out; + ecryptfs_dentry->d_name.name, rc); + goto out_free_kmem; } } + crypt_stat = &ecryptfs_inode_to_private( + ecryptfs_dentry->d_inode)->crypt_stat; + /* TODO: lock for crypt_stat comparison */ + if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) + ecryptfs_set_default_sizes(crypt_stat); rc = ecryptfs_read_and_validate_header_region(page_virt, - dentry->d_inode); + ecryptfs_dentry->d_inode); if (rc) { - rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry); + memset(page_virt, 0, PAGE_CACHE_SIZE); + rc = ecryptfs_read_and_validate_xattr_region(page_virt, + ecryptfs_dentry); if (rc) { - printk(KERN_DEBUG "Valid metadata not found in header " - "region or xattr region; treating file as " - "unencrypted\n"); rc = 0; - kmem_cache_free(ecryptfs_header_cache_2, page_virt); - goto out; + goto out_free_kmem; } crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; } mount_crypt_stat = &ecryptfs_superblock_to_private( - dentry->d_sb)->mount_crypt_stat; + ecryptfs_dentry->d_sb)->mount_crypt_stat; if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) - file_size = (crypt_stat->num_header_bytes_at_front + file_size = (crypt_stat->metadata_size + i_size_read(lower_dentry->d_inode)); else file_size = i_size_read(lower_dentry->d_inode); } else { file_size = get_unaligned_be64(page_virt); } - i_size_write(dentry->d_inode, (loff_t)file_size); + i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size); +out_free_kmem: kmem_cache_free(ecryptfs_header_cache_2, page_virt); goto out; - out_dput: dput(lower_dentry); - d_drop(dentry); + d_drop(ecryptfs_dentry); +out: + return rc; +} + +/** + * ecryptfs_lookup + * @ecryptfs_dir_inode: The eCryptfs directory inode + * @ecryptfs_dentry: The eCryptfs dentry that we are looking up + * @ecryptfs_nd: nameidata; may be NULL + * + * Find a file on disk. If the file does not exist, then we'll add it to the + * dentry cache and continue on to read it from the disk. + */ +static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, + struct dentry *ecryptfs_dentry, + struct nameidata *ecryptfs_nd) +{ + char *encrypted_and_encoded_name = NULL; + size_t encrypted_and_encoded_name_size; + struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; + struct dentry *lower_dir_dentry, *lower_dentry; + int rc = 0; + + ecryptfs_dentry->d_op = &ecryptfs_dops; + if ((ecryptfs_dentry->d_name.len == 1 + && !strcmp(ecryptfs_dentry->d_name.name, ".")) + || (ecryptfs_dentry->d_name.len == 2 + && !strcmp(ecryptfs_dentry->d_name.name, ".."))) { + 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); + ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned " + "[%d] on lower_dentry = [%s]\n", __func__, rc, + encrypted_and_encoded_name); + goto out_d_drop; + } + if (lower_dentry->d_inode) + goto lookup_and_interpose; + mount_crypt_stat = &ecryptfs_superblock_to_private( + ecryptfs_dentry->d_sb)->mount_crypt_stat; + if (!(mount_crypt_stat + && (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES))) + goto lookup_and_interpose; + dput(lower_dentry); + rc = ecryptfs_encrypt_and_encode_filename( + &encrypted_and_encoded_name, &encrypted_and_encoded_name_size, + NULL, mount_crypt_stat, ecryptfs_dentry->d_name.name, + ecryptfs_dentry->d_name.len); + if (rc) { + printk(KERN_ERR "%s: Error attempting to encrypt and encode " + "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); + ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned " + "[%d] on lower_dentry = [%s]\n", __func__, rc, + encrypted_and_encoded_name); + goto out_d_drop; + } +lookup_and_interpose: + rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry, + ecryptfs_dir_inode, + ecryptfs_nd); + goto out; +out_d_drop: + d_drop(ecryptfs_dentry); out: + kfree(encrypted_and_encoded_name); return ERR_PTR(rc); } @@ -421,8 +448,8 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir, rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0); if (rc) goto out_lock; - fsstack_copy_attr_times(dir, lower_new_dentry->d_inode); - fsstack_copy_inode_size(dir, lower_new_dentry->d_inode); + fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode); + fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode); old_dentry->d_inode->i_nlink = ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink; i_size_write(new_dentry->d_inode, file_size_save); @@ -430,9 +457,6 @@ 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; } @@ -443,6 +467,7 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir); struct dentry *lower_dir_dentry; + dget(lower_dentry); lower_dir_dentry = lock_parent(lower_dentry); rc = vfs_unlink(lower_dir_inode, lower_dentry); if (rc) { @@ -456,6 +481,7 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry) d_drop(dentry); out_unlock: unlock_dir(lower_dir_dentry); + dput(lower_dentry); return rc; } @@ -466,19 +492,21 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, struct dentry *lower_dentry; struct dentry *lower_dir_dentry; char *encoded_symname; - int encoded_symlen; - struct ecryptfs_crypt_stat *crypt_stat = NULL; + size_t encoded_symlen; + struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; lower_dentry = ecryptfs_dentry_to_lower(dentry); dget(lower_dentry); lower_dir_dentry = lock_parent(lower_dentry); - encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname, - strlen(symname), - &encoded_symname); - if (encoded_symlen < 0) { - rc = encoded_symlen; + mount_crypt_stat = &ecryptfs_superblock_to_private( + dir->i_sb)->mount_crypt_stat; + rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname, + &encoded_symlen, + NULL, + mount_crypt_stat, symname, + strlen(symname)); + if (rc) goto out_lock; - } rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, encoded_symname); kfree(encoded_symname); @@ -577,6 +605,7 @@ 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); @@ -584,14 +613,24 @@ 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); @@ -601,57 +640,51 @@ out_lock: return rc; } -static int -ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz) +static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf, + size_t *bufsiz) { - int rc; - struct dentry *lower_dentry; - char *decoded_name; + struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); char *lower_buf; + size_t lower_bufsiz = PATH_MAX; mm_segment_t old_fs; - struct ecryptfs_crypt_stat *crypt_stat; + int rc; - lower_dentry = ecryptfs_dentry_to_lower(dentry); - if (!lower_dentry->d_inode->i_op || - !lower_dentry->d_inode->i_op->readlink) { - rc = -EINVAL; - goto out; - } - /* Released in this function */ - lower_buf = kmalloc(bufsiz, GFP_KERNEL); - if (lower_buf == NULL) { - ecryptfs_printk(KERN_ERR, "Out of memory\n"); + lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL); + if (!lower_buf) { rc = -ENOMEM; goto out; } old_fs = get_fs(); set_fs(get_ds()); - ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " - "lower_dentry->d_name.name = [%s]\n", - lower_dentry->d_name.name); rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, (char __user *)lower_buf, - bufsiz); + lower_bufsiz); set_fs(old_fs); - if (rc >= 0) { - crypt_stat = NULL; - rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc, - &decoded_name); - if (rc == -ENOMEM) - goto out_free_lower_buf; - if (rc > 0) { - ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes " - "to userspace: [%*s]\n", rc, - decoded_name); - if (copy_to_user(buf, decoded_name, rc)) - rc = -EFAULT; - } - kfree(decoded_name); - fsstack_copy_attr_atime(dentry->d_inode, - lower_dentry->d_inode); - } -out_free_lower_buf: + if (rc < 0) + goto out; + lower_bufsiz = rc; + rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry, + lower_buf, lower_bufsiz); +out: kfree(lower_buf); + return rc; +} + +static int +ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz) +{ + char *kbuf; + size_t kbufsiz, copied; + int rc; + + rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz); + if (rc) + goto out; + copied = min_t(size_t, bufsiz, kbufsiz); + rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied; + kfree(kbuf); + fsstack_copy_attr_atime(dentry->d_inode, + ecryptfs_dentry_to_lower(dentry)->d_inode); out: return rc; } @@ -665,32 +698,31 @@ 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()); - ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " - "dentry->d_name.name = [%s]\n", dentry->d_name.name); rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); - buf[rc] = '\0'; set_fs(old_fs); - if (rc < 0) - goto out_free; - rc = 0; - nd_set_link(nd, buf); - goto out; -out_free: - kfree(buf); + if (rc < 0) { + kfree(buf); + buf = ERR_PTR(rc); + } else + buf[rc] = '\0'; 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); + } } /** @@ -710,7 +742,7 @@ upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat, { loff_t lower_size; - lower_size = crypt_stat->num_header_bytes_at_front; + lower_size = ecryptfs_lower_header_size(crypt_stat); if (upper_size != 0) { loff_t num_extents; @@ -723,110 +755,132 @@ 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; - struct dentry *lower_dentry; - struct file fake_ecryptfs_file; struct ecryptfs_crypt_stat *crypt_stat; loff_t i_size = i_size_read(inode); loff_t lower_size_before_truncate; loff_t lower_size_after_truncate; - if (unlikely((new_length == i_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 - * truncation has an effect there as well. */ - memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file)); - fake_ecryptfs_file.f_path.dentry = dentry; - /* Released at out_free: label */ - ecryptfs_set_file_private(&fake_ecryptfs_file, - kmem_cache_alloc(ecryptfs_file_info_cache, - GFP_KERNEL)); - if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) { - rc = -ENOMEM; + if (unlikely((ia->ia_size == i_size))) { + lower_ia->ia_valid &= ~ATTR_SIZE; goto out; } - lower_dentry = ecryptfs_dentry_to_lower(dentry); - ecryptfs_set_file_lower( - &fake_ecryptfs_file, - ecryptfs_inode_to_private(dentry->d_inode)->lower_file); + crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; /* 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 + rc = ecryptfs_write(inode, zero, + (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, ia->ia_size); + if (rc) + goto out; + lower_ia->ia_size = ia->ia_size; + lower_ia->ia_valid |= ATTR_SIZE; + goto out; + } if (num_zeros) { char *zeros_virt; zeros_virt = kzalloc(num_zeros, GFP_KERNEL); if (!zeros_virt) { rc = -ENOMEM; - goto out_free; + goto out; } - rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt, - new_length, num_zeros); + rc = ecryptfs_write(inode, zeros_virt, + ia->ia_size, num_zeros); kfree(zeros_virt); if (rc) { printk(KERN_ERR "Error attempting to zero out " "the remainder of the end page on " "reducing truncate; rc = [%d]\n", rc); - goto out_free; + goto out; } } - vmtruncate(inode, new_length); + vmtruncate(inode, ia->ia_size); rc = ecryptfs_write_inode_size_to_metadata(inode); if (rc) { printk(KERN_ERR "Problem with " "ecryptfs_write_inode_size_to_metadata; " "rc = [%d]\n", rc); - goto out_free; + goto out; } /* We are reducing the size of the ecryptfs file, and need to * know if we need to reduce the size of the lower file. */ 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)) - kmem_cache_free(ecryptfs_file_info_cache, - ecryptfs_file_to_private(&fake_ecryptfs_file)); 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) { @@ -849,6 +903,7 @@ 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; @@ -884,20 +939,14 @@ 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); + 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; } @@ -906,14 +955,51 @@ 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_link(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat) +{ + struct ecryptfs_mount_crypt_stat *mount_crypt_stat; + int rc = 0; + + mount_crypt_stat = &ecryptfs_superblock_to_private( + dentry->d_sb)->mount_crypt_stat; + generic_fillattr(dentry->d_inode, stat); + if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) { + char *target; + size_t targetsiz; + + rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz); + if (!rc) { + kfree(target); + stat->size = targetsiz; + } + } + 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; } @@ -926,7 +1012,7 @@ ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value, lower_dentry = ecryptfs_dentry_to_lower(dentry); if (!lower_dentry->d_inode->i_op->setxattr) { - rc = -ENOSYS; + rc = -EOPNOTSUPP; goto out; } mutex_lock(&lower_dentry->d_inode->i_mutex); @@ -944,7 +1030,7 @@ ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name, int rc = 0; if (!lower_dentry->d_inode->i_op->getxattr) { - rc = -ENOSYS; + rc = -EOPNOTSUPP; goto out; } mutex_lock(&lower_dentry->d_inode->i_mutex); @@ -971,7 +1057,7 @@ ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size) lower_dentry = ecryptfs_dentry_to_lower(dentry); if (!lower_dentry->d_inode->i_op->listxattr) { - rc = -ENOSYS; + rc = -EOPNOTSUPP; goto out; } mutex_lock(&lower_dentry->d_inode->i_mutex); @@ -988,7 +1074,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, const char *name) lower_dentry = ecryptfs_dentry_to_lower(dentry); if (!lower_dentry->d_inode->i_op->removexattr) { - rc = -ENOSYS; + rc = -EOPNOTSUPP; goto out; } mutex_lock(&lower_dentry->d_inode->i_mutex); @@ -1019,6 +1105,7 @@ const struct inode_operations ecryptfs_symlink_iops = { .put_link = ecryptfs_put_link, .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, + .getattr = ecryptfs_getattr_link, .setxattr = ecryptfs_setxattr, .getxattr = ecryptfs_getxattr, .listxattr = ecryptfs_listxattr, @@ -1046,6 +1133,7 @@ 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,