diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 7733e29433678fad16c22687184bd9ece4705be4..c7c42c9c7bf708d79fa3db174675df13303f85dc 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2266,7 +2266,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); ext4_ext_dirty(handle, inode, path + depth); - return le16_to_cpu(ex->ee_len); + /* zeroed the full extent */ + return allocated; } /* ex1: ee_block to iblock - 1 : uninitialized */ @@ -2311,11 +2312,45 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); ext4_ext_dirty(handle, inode, path + depth); - return le16_to_cpu(ex->ee_len); + /* zeroed the full extent */ + return allocated; } else if (err) goto fix_extent_len; + /* + * We need to zero out the second half because + * an fallocate request can update file size and + * converting the second half to initialized extent + * implies that we can leak some junk data to user + * space. + */ + err = ext4_ext_zeroout(inode, ex3); + if (err) { + /* + * We should actually mark the + * second half as uninit and return error + * Insert would have changed the extent + */ + depth = ext_depth(inode); + ext4_ext_drop_refs(path); + path = ext4_ext_find_extent(inode, + iblock, path); + if (IS_ERR(path)) { + err = PTR_ERR(path); + return err; + } + ex = path[depth].p_ext; + err = ext4_ext_get_access(handle, inode, + path + depth); + if (err) + return err; + ext4_ext_mark_uninitialized(ex); + ext4_ext_dirty(handle, inode, path + depth); + return err; + } + + /* zeroed the second half */ return allocated; } ex3 = &newex; @@ -2333,7 +2368,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); ext4_ext_dirty(handle, inode, path + depth); - return le16_to_cpu(ex->ee_len); + /* zeroed the full extent */ + return allocated; } else if (err) goto fix_extent_len; @@ -2381,7 +2417,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); ext4_ext_dirty(handle, inode, path + depth); - return le16_to_cpu(ex->ee_len); + /* zero out the first half */ + return allocated; } } /* @@ -2448,7 +2485,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); ext4_ext_dirty(handle, inode, path + depth); - return le16_to_cpu(ex->ee_len); + /* zero out the first half */ + return allocated; } else if (err) goto fix_extent_len; out: