diff options
| -rw-r--r-- | fs/ubifs/dir.c | 7 | ||||
| -rw-r--r-- | fs/ubifs/journal.c | 1 | ||||
| -rw-r--r-- | fs/ubifs/tnc.c | 90 | ||||
| -rw-r--r-- | fs/ubifs/ubifs-media.h | 5 | ||||
| -rw-r--r-- | fs/ubifs/ubifs.h | 2 |
5 files changed, 98 insertions, 7 deletions
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 7d3bc3fb8831..7f01f3d2ac3b 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -253,7 +253,7 @@ static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry, ubifs_assert(fname_len(&nm) == 0); ubifs_assert(fname_name(&nm) == NULL); dent_key_init_hash(c, &key, dir->i_ino, nm.hash); - err = ubifs_tnc_lookup(c, &key, dent); + err = ubifs_tnc_lookup_dh(c, &key, dent, nm.minor_hash); } else { dent_key_init(c, &key, dir->i_ino, &nm); err = ubifs_tnc_lookup_nm(c, &key, dent, &nm); @@ -628,7 +628,10 @@ static int ubifs_readdir(struct file *file, struct dir_context *ctx) if (encrypted) { fstr.len = fstr_real_len; - err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c, &dent->key), 0, &nm.disk_name, &fstr); + err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c, + &dent->key), + le32_to_cpu(dent->cookie), + &nm.disk_name, &fstr); if (err) goto out; } else { diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c index f2b989dbe25a..0698cccc6223 100644 --- a/fs/ubifs/journal.c +++ b/fs/ubifs/journal.c @@ -78,7 +78,6 @@ static inline void zero_ino_node_unused(struct ubifs_ino_node *ino) static inline void zero_dent_node_unused(struct ubifs_dent_node *dent) { dent->padding1 = 0; - memset(dent->padding2, 0, 4); } /** diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c index 0d751297873e..1bba4c8b5d3d 100644 --- a/fs/ubifs/tnc.c +++ b/fs/ubifs/tnc.c @@ -1783,7 +1783,7 @@ int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu) * @node: the node is returned here * @nm: node name * - * This function look up and reads a node which contains name hash in the key. + * This function looks up and reads a node which contains name hash in the key. * Since the hash may have collisions, there may be many nodes with the same * key, so we have to sequentially look to all of them until the needed one is * found. This function returns zero in case of success, %-ENOENT if the node @@ -1831,7 +1831,7 @@ out_unlock: * @node: the node is returned here * @nm: node name * - * This function look up and reads a node which contains name hash in the key. + * This function looks up and reads a node which contains name hash in the key. * Since the hash may have collisions, there may be many nodes with the same * key, so we have to sequentially look to all of them until the needed one is * found. This function returns zero in case of success, %-ENOENT if the node @@ -1859,9 +1859,95 @@ int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, * Unluckily, there are hash collisions and we have to iterate over * them look at each direntry with colliding name hash sequentially. */ + return do_lookup_nm(c, key, node, nm); } +static int do_lookup_dh(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_dent_node *dent, uint32_t cookie) +{ + int n, err, type = key_type(c, key); + struct ubifs_znode *znode; + struct ubifs_zbranch *zbr; + union ubifs_key *dkey, start_key; + + ubifs_assert(is_hash_key(c, key)); + + lowest_dent_key(c, &start_key, key_inum(c, key)); + + mutex_lock(&c->tnc_mutex); + err = ubifs_lookup_level0(c, &start_key, &znode, &n); + if (unlikely(err < 0)) + goto out_unlock; + + for (;;) { + if (!err) { + err = tnc_next(c, &znode, &n); + if (err) + goto out_unlock; + } + + zbr = &znode->zbranch[n]; + dkey = &zbr->key; + + if (key_inum(c, dkey) != key_inum(c, key) || + key_type(c, dkey) != type) { + err = -ENOENT; + goto out_unlock; + } + + err = tnc_read_hashed_node(c, zbr, dent); + if (err) + goto out_unlock; + + if (key_hash(c, key) == key_hash(c, dkey) && + le32_to_cpu(dent->cookie) == cookie) + goto out_unlock; + } + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_lookup_dh - look up a "double hashed" node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @cookie: node cookie for collision resolution + * + * This function looks up and reads a node which contains name hash in the key. + * Since the hash may have collisions, there may be many nodes with the same + * key, so we have to sequentially look to all of them until the needed one + * with the same cookie value is found. + * This function returns zero in case of success, %-ENOENT if the node + * was not found, and a negative error code in case of failure. + */ +int ubifs_tnc_lookup_dh(struct ubifs_info *c, const union ubifs_key *key, + void *node, uint32_t cookie) +{ + int err; + const struct ubifs_dent_node *dent = node; + + /* + * We assume that in most of the cases there are no name collisions and + * 'ubifs_tnc_lookup()' returns us the right direntry. + */ + err = ubifs_tnc_lookup(c, key, node); + if (err) + return err; + + if (le32_to_cpu(dent->cookie) == cookie) + return 0; + + /* + * Unluckily, there are hash collisions and we have to iterate over + * them look at each direntry with colliding name hash sequentially. + */ + return do_lookup_dh(c, key, node, cookie); +} + /** * correct_parent_keys - correct parent znodes' keys. * @c: UBIFS file-system description object diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h index e46331dcca4c..249124d9a801 100644 --- a/fs/ubifs/ubifs-media.h +++ b/fs/ubifs/ubifs-media.h @@ -530,7 +530,8 @@ struct ubifs_ino_node { * @padding1: reserved for future, zeroes * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc) * @nlen: name length - * @padding2: reserved for future, zeroes + * @cookie: A 32bits random number, used to construct a 64bits + * identifier. * @name: zero-terminated name * * Note, do not forget to amend 'zero_dent_node_unused()' function when @@ -543,7 +544,7 @@ struct ubifs_dent_node { __u8 padding1; __u8 type; __le16 nlen; - __u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */ + __le32 cookie; __u8 name[]; } __packed; diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h index 8ccd19257a81..a80610758543 100644 --- a/fs/ubifs/ubifs.h +++ b/fs/ubifs/ubifs.h @@ -1571,6 +1571,8 @@ int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key, struct ubifs_znode **zn, int *n); int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, void *node, const struct fscrypt_name *nm); +int ubifs_tnc_lookup_dh(struct ubifs_info *c, const union ubifs_key *key, + void *node, uint32_t secondary_hash); int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key, void *node, int *lnum, int *offs); int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum, |