diff options
Diffstat (limited to 'lib/stdlib/src/erl_tar.erl')
| -rw-r--r-- | lib/stdlib/src/erl_tar.erl | 65 |
1 files changed, 45 insertions, 20 deletions
diff --git a/lib/stdlib/src/erl_tar.erl b/lib/stdlib/src/erl_tar.erl index 086e77cd28..168ea4002c 100644 --- a/lib/stdlib/src/erl_tar.erl +++ b/lib/stdlib/src/erl_tar.erl @@ -69,6 +69,8 @@ format_error(invalid_gnu_1_0_sparsemap) -> "Invalid GNU sparse map (version 1.0)"; format_error({invalid_gnu_0_1_sparsemap, Format}) -> lists:flatten(io_lib:format("Invalid GNU sparse map (version ~s)", [Format])); +format_error(unsafe_path) -> + "The path points above the current working directory"; format_error({Name,Reason}) -> lists:flatten(io_lib:format("~ts: ~ts", [Name,format_error(Reason)])); format_error(Atom) when is_atom(Atom) -> @@ -120,26 +122,38 @@ do_extract(Handle, Opts) when is_list(Opts) -> extract1(eof, Reader, _, Acc) when is_list(Acc) -> {ok, {ok, lists:reverse(Acc)}, Reader}; +extract1(eof, Reader, _, leading_slash) -> + error_logger:info_msg("erl_tar: removed leading '/' from member names\n"), + {ok, ok, Reader}; extract1(eof, Reader, _, Acc) -> {ok, Acc, Reader}; -extract1(#tar_header{name=Name,size=Size}=Header, Reader, Opts, Acc) -> +extract1(#tar_header{name=Name,size=Size}=Header, Reader0, Opts, Acc0) -> case check_extract(Name, Opts) of true -> - case do_read(Reader, Size) of - {ok, Bin, Reader2} -> - case write_extracted_element(Header, Bin, Opts) of - ok -> - {ok, Acc, Reader2}; - {ok, NameBin} when is_list(Acc) -> - {ok, [NameBin | Acc], Reader2}; - {error, _} = Err -> - throw(Err) - end; + case do_read(Reader0, Size) of + {ok, Bin, Reader1} -> + Acc = extract2(Header, Bin, Opts, Acc0), + {ok, Acc, Reader1}; {error, _} = Err -> throw(Err) end; false -> - {ok, Acc, skip_file(Reader)} + {ok, Acc0, skip_file(Reader0)} + end. + +extract2(Header, Bin, Opts, Acc) -> + case write_extracted_element(Header, Bin, Opts) of + ok -> + case Header of + #tar_header{name="/"++_} -> + leading_slash; + #tar_header{} -> + Acc + end; + {ok, NameBin} when is_list(Acc) -> + [NameBin | Acc]; + {error, _} = Err -> + throw(Err) end. %% Checks if the file Name should be extracted. @@ -1052,14 +1066,11 @@ unpack_modern(Format, #header_v7{}=V7, Bin, #tar_header{}=Header0) safe_join_path([], Name) -> - strip_slashes(Name, both); + filename:join([Name]); safe_join_path(Prefix, []) -> - strip_slashes(Prefix, right); + filename:join([Prefix]); safe_join_path(Prefix, Name) -> - filename:join(strip_slashes(Prefix, right), strip_slashes(Name, both)). - -strip_slashes(Str, Direction) -> - string:strip(Str, Direction, $/). + filename:join(Prefix, Name). new_sparse_file_reader(Reader, Sparsemap, RealSize) -> true = validate_sparse_entries(Sparsemap, RealSize), @@ -1321,7 +1332,11 @@ foldl_read(TarName, Fun, Accu, #read_opts{}=Opts) when is_function(Fun,4) -> try open(TarName, [read|Opts#read_opts.open_mode]) of {ok, #reader{access=read}=Reader} -> - foldl_read(Reader, Fun, Accu, Opts); + try + foldl_read(Reader, Fun, Accu, Opts) + after + _ = close(Reader) + end; {error, _} = Err -> Err catch @@ -1553,7 +1568,7 @@ write_extracted_element(#tar_header{name=Name,typeflag=Type}, ok end; write_extracted_element(#tar_header{name=Name0}=Header, Bin, Opts) -> - Name1 = filename:absname(Name0, Opts#read_opts.cwd), + Name1 = make_safe_path(Name0, Opts), Created = case typeflag(Header#tar_header.typeflag) of regular -> @@ -1581,6 +1596,16 @@ write_extracted_element(#tar_header{name=Name0}=Header, Bin, Opts) -> not_written -> ok end. +make_safe_path([$/|Path], Opts) -> + make_safe_path(Path, Opts); +make_safe_path(Path, #read_opts{cwd=Cwd}) -> + case filename:safe_relative_path(Path) of + unsafe -> + throw({error,{Path,unsafe_path}}); + SafePath -> + filename:absname(SafePath, Cwd) + end. + create_regular(Name, NameInArchive, Bin, Opts) -> case write_extracted_file(Name, Bin, Opts) of not_written -> |