diff options
| -rw-r--r-- | fs/ext4/namei.c | 291 |
1 files changed, 119 insertions, 172 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 3e1529c39808..0e28c749e273 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -83,6 +83,86 @@ static struct buffer_head *ext4_append(handle_t *handle, return bh; } +static int ext4_dx_csum_verify(struct inode *inode, + struct ext4_dir_entry *dirent); + +typedef enum { + EITHER, INDEX, DIRENT +} dirblock_type_t; + +#define ext4_read_dirblock(inode, block, type) \ + __ext4_read_dirblock((inode), (block), (type), __LINE__) + +static struct buffer_head *__ext4_read_dirblock(struct inode *inode, + ext4_lblk_t block, + dirblock_type_t type, + unsigned int line) +{ + struct buffer_head *bh; + struct ext4_dir_entry *dirent; + int err = 0, is_dx_block = 0; + + bh = ext4_bread(NULL, inode, block, 0, &err); + if (!bh) { + if (err == 0) { + ext4_error_inode(inode, __func__, line, block, + "Directory hole found"); + return ERR_PTR(-EIO); + } + __ext4_warning(inode->i_sb, __func__, line, + "error reading directory block " + "(ino %lu, block %lu)", inode->i_ino, + (unsigned long) block); + return ERR_PTR(err); + } + dirent = (struct ext4_dir_entry *) bh->b_data; + /* Determine whether or not we have an index block */ + if (is_dx(inode)) { + if (block == 0) + is_dx_block = 1; + else if (ext4_rec_len_from_disk(dirent->rec_len, + inode->i_sb->s_blocksize) == + inode->i_sb->s_blocksize) + is_dx_block = 1; + } + if (!is_dx_block && type == INDEX) { + ext4_error_inode(inode, __func__, line, block, + "directory leaf block found instead of index block"); + return ERR_PTR(-EIO); + } + if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) || + buffer_verified(bh)) + return bh; + + /* + * An empty leaf block can get mistaken for a index block; for + * this reason, we can only check the index checksum when the + * caller is sure it should be an index block. + */ + if (is_dx_block && type == INDEX) { + if (ext4_dx_csum_verify(inode, dirent)) + set_buffer_verified(bh); + else { + ext4_error_inode(inode, __func__, line, block, + "Directory index failed checksum"); + brelse(bh); + return ERR_PTR(-EIO); + } + } + if (!is_dx_block) { + if (ext4_dirent_csum_verify(inode, dirent)) + set_buffer_verified(bh); + else { + ext4_error_inode(inode, __func__, line, block, + "Directory block failed checksum"); + brelse(bh); + return ERR_PTR(-EIO); + } + } + return bh; +} + #ifndef assert #define assert(test) J_ASSERT(test) #endif @@ -604,9 +684,9 @@ dx_probe(const struct qstr *d_name, struct inode *dir, u32 hash; frame->bh = NULL; - if (!(bh = ext4_bread(NULL, dir, 0, 0, err))) { - if (*err == 0) - *err = ERR_BAD_DX_DIR; + bh = ext4_read_dirblock(dir, 0, INDEX); + if (IS_ERR(bh)) { + *err = PTR_ERR(bh); goto fail; } root = (struct dx_root *) bh->b_data; @@ -643,15 +723,6 @@ dx_probe(const struct qstr *d_name, struct inode *dir, goto fail; } - if (!buffer_verified(bh) && - !ext4_dx_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data)) { - ext4_warning(dir->i_sb, "Root failed checksum"); - brelse(bh); - *err = ERR_BAD_DX_DIR; - goto fail; - } - set_buffer_verified(bh); - entries = (struct dx_entry *) (((char *)&root->info) + root->info.info_length); @@ -709,23 +780,13 @@ dx_probe(const struct qstr *d_name, struct inode *dir, frame->entries = entries; frame->at = at; if (!indirect--) return frame; - if (!(bh = ext4_bread(NULL, dir, dx_get_block(at), 0, err))) { - if (!(*err)) - *err = ERR_BAD_DX_DIR; + bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); + if (IS_ERR(bh)) { + *err = PTR_ERR(bh); goto fail2; } entries = ((struct dx_node *) bh->b_data)->entries; - if (!buffer_verified(bh) && - !ext4_dx_csum_verify(dir, - (struct ext4_dir_entry *)bh->b_data)) { - ext4_warning(dir->i_sb, "Node failed checksum"); - brelse(bh); - *err = ERR_BAD_DX_DIR; - goto fail2; - } - set_buffer_verified(bh); - if (dx_get_limit(entries) != dx_node_limit (dir)) { ext4_warning(dir->i_sb, "dx entry: limit != node limit"); @@ -783,7 +844,7 @@ static int ext4_htree_next_block(struct inode *dir, __u32 hash, { struct dx_frame *p; struct buffer_head *bh; - int err, num_frames = 0; + int num_frames = 0; __u32 bhash; p = frame; @@ -822,26 +883,9 @@ static int ext4_htree_next_block(struct inode *dir, __u32 hash, * block so no check is necessary */ while (num_frames--) { - if (!(bh = ext4_bread(NULL, dir, dx_get_block(p->at), - 0, &err))) { - if (!err) { - ext4_error(dir->i_sb, - "Directory hole detected on inode %lu\n", - dir->i_ino); - return -EIO; - } - return err; /* Failure */ - } - - if (!buffer_verified(bh) && - !ext4_dx_csum_verify(dir, - (struct ext4_dir_entry *)bh->b_data)) { - ext4_warning(dir->i_sb, "Node failed checksum"); - brelse(bh); - return -EIO; - } - set_buffer_verified(bh); - + bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); + if (IS_ERR(bh)) + return PTR_ERR(bh); p++; brelse(p->bh); p->bh = bh; @@ -867,23 +911,9 @@ static int htree_dirblock_to_tree(struct file *dir_file, dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", (unsigned long)block)); - if (!(bh = ext4_bread(NULL, dir, block, 0, &err))) { - if (!err) { - err = -EIO; - ext4_error(dir->i_sb, - "Directory hole detected on inode %lu\n", - dir->i_ino); - } - return err; - } - - if (!buffer_verified(bh) && - !ext4_dirent_csum_verify(dir, - (struct ext4_dir_entry *)bh->b_data)) { - brelse(bh); - return -EIO; - } - set_buffer_verified(bh); + bh = ext4_read_dirblock(dir, block, DIRENT); + if (IS_ERR(bh)) + return PTR_ERR(bh); de = (struct ext4_dir_entry_2 *) bh->b_data; top = (struct ext4_dir_entry_2 *) ((char *) de + @@ -1337,26 +1367,11 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct q return NULL; do { block = dx_get_block(frame->at); - if (!(bh = ext4_bread(NULL, dir, block, 0, err))) { - if (!(*err)) { - *err = -EIO; - ext4_error(dir->i_sb, - "Directory hole detected on inode %lu\n", - dir->i_ino); - } + bh = ext4_read_dirblock(dir, block, DIRENT); + if (IS_ERR(bh)) { + *err = PTR_ERR(bh); goto errout; } - - if (!buffer_verified(bh) && - !ext4_dirent_csum_verify(dir, - (struct ext4_dir_entry *)bh->b_data)) { - EXT4_ERROR_INODE(dir, "checksumming directory " - "block %lu", (unsigned long)block); - brelse(bh); - *err = -EIO; - goto errout; - } - set_buffer_verified(bh); retval = search_dirblock(bh, dir, d_name, block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); @@ -1920,22 +1935,10 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, } blocks = dir->i_size >> sb->s_blocksize_bits; for (block = 0; block < blocks; block++) { - if (!(bh = ext4_bread(handle, dir, block, 0, &retval))) { - if (!retval) { - retval = -EIO; - ext4_error(inode->i_sb, - "Directory hole detected on inode %lu\n", - inode->i_ino); - } - return retval; - } - if (!buffer_verified(bh) && - !ext4_dirent_csum_verify(dir, - (struct ext4_dir_entry *)bh->b_data)) { - brelse(bh); - return -EIO; - } - set_buffer_verified(bh); + bh = ext4_read_dirblock(dir, block, DIRENT); + if (IS_ERR(bh)) + return PTR_ERR(bh); + retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); if (retval != -ENOSPC) { brelse(bh); @@ -1986,22 +1989,13 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry, return err; entries = frame->entries; at = frame->at; - - if (!(bh = ext4_bread(handle, dir, dx_get_block(frame->at), 0, &err))) { - if (!err) { - err = -EIO; - ext4_error(dir->i_sb, - "Directory hole detected on inode %lu\n", - dir->i_ino); - } + bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); + if (IS_ERR(bh)) { + err = PTR_ERR(bh); + bh = NULL; goto cleanup; } - if (!buffer_verified(bh) && - !ext4_dirent_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data)) - goto journal_error; - set_buffer_verified(bh); - BUFFER_TRACE(bh, "get_write_access"); err = ext4_journal_get_write_access(handle, bh); if (err) @@ -2352,6 +2346,7 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir, struct buffer_head *dir_block = NULL; struct ext4_dir_entry_2 *de; struct ext4_dir_entry_tail *t; + ext4_lblk_t block = 0; unsigned int blocksize = dir->i_sb->s_blocksize; int csum_size = 0; int err; @@ -2368,16 +2363,9 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir, goto out; } - inode->i_size = EXT4_I(inode)->i_disksize = blocksize; - if (!(dir_block = ext4_bread(handle, inode, 0, 1, &err))) { - if (!err) { - err = -EIO; - ext4_error(inode->i_sb, - "Directory hole detected on inode %lu\n", - inode->i_ino); - } + inode->i_size = 0; + if (!(dir_block = ext4_append(handle, inode, &block, &err))) goto out; - } BUFFER_TRACE(dir_block, "get_write_access"); err = ext4_journal_get_write_access(handle, dir_block); if (err) @@ -2477,26 +2465,14 @@ static int empty_dir(struct inode *inode) } sb = inode->i_sb; - if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2) || - !(bh = ext4_bread(NULL, inode, 0, 0, &err))) { - if (err) - EXT4_ERROR_INODE(inode, - "error %d reading directory lblock 0", err); - else - ext4_warning(inode->i_sb, - "bad directory (dir #%lu) - no data block", - inode->i_ino); + if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { + EXT4_ERROR_INODE(inode, "invalid size"); return 1; } - if (!buffer_verified(bh) && - !ext4_dirent_csum_verify(inode, - (struct ext4_dir_entry *)bh->b_data)) { - EXT4_ERROR_INODE(inode, "checksum error reading directory " - "lblock 0"); - brelse(bh); - return -EIO; - } - set_buffer_verified(bh); + bh = ext4_read_dirblock(inode, 0, EITHER); + if (IS_ERR(bh)) + return 1; + de = (struct ext4_dir_entry_2 *) bh->b_data; de1 = ext4_next_entry(de, sb->s_blocksize); if (le32_to_cpu(de->inode) != inode->i_ino || @@ -2519,29 +2495,9 @@ static int empty_dir(struct inode *inode) err = 0; brelse(bh); lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); - bh = ext4_bread(NULL, inode, lblock, 0, &err); - if (!bh) { - if (err) - EXT4_ERROR_INODE(inode, - "error %d reading directory " - "lblock %u", err, lblock); - else - ext4_warning(inode->i_sb, - "bad directory (dir #%lu) - no data block", - inode->i_ino); - - offset += sb->s_blocksize; - continue; - } - if (!buffer_verified(bh) && - !ext4_dirent_csum_verify(inode, - (struct ext4_dir_entry *)bh->b_data)) { - EXT4_ERROR_INODE(inode, "checksum error " - "reading directory lblock 0"); - brelse(bh); - return -EIO; - } - set_buffer_verified(bh); + bh = ext4_read_dirblock(inode, lblock, EITHER); + if (IS_ERR(bh)) + return 1; de = (struct ext4_dir_entry_2 *) bh->b_data; } if (ext4_check_dir_entry(inode, NULL, de, bh, @@ -3004,13 +2960,9 @@ static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, struct buffer_head *bh; if (!ext4_has_inline_data(inode)) { - if (!(bh = ext4_bread(handle, inode, 0, 0, retval))) { - if (!*retval) { - *retval = -EIO; - ext4_error(inode->i_sb, - "Directory hole detected on inode %lu\n", - inode->i_ino); - } + bh = ext4_read_dirblock(inode, 0, EITHER); + if (IS_ERR(bh)) { + *retval = PTR_ERR(bh); return NULL; } *parent_de = ext4_next_entry( @@ -3089,11 +3041,6 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, &inlined); if (!dir_bh) goto end_rename; - if (!inlined && !buffer_verified(dir_bh) && - !ext4_dirent_csum_verify(old_inode, - (struct ext4_dir_entry *)dir_bh->b_data)) - goto end_rename; - set_buffer_verified(dir_bh); if (le32_to_cpu(parent_de->inode) != old_dir->i_ino) goto end_rename; retval = -EMLINK; |