diff options
Diffstat (limited to 'src/archive/tar/reader.go')
| -rw-r--r-- | src/archive/tar/reader.go | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/archive/tar/reader.go b/src/archive/tar/reader.go index 4b11909bc9..e609c15f27 100644 --- a/src/archive/tar/reader.go +++ b/src/archive/tar/reader.go @@ -103,7 +103,7 @@ func (tr *Reader) next() (*Header, error) { continue // This is a meta header affecting the next header case TypeGNULongName, TypeGNULongLink: format.mayOnlyBe(FormatGNU) - realname, err := io.ReadAll(tr) + realname, err := readSpecialFile(tr) if err != nil { return nil, err } @@ -293,7 +293,7 @@ func mergePAX(hdr *Header, paxHdrs map[string]string) (err error) { // parsePAX parses PAX headers. // If an extended header (type 'x') is invalid, ErrHeader is returned func parsePAX(r io.Reader) (map[string]string, error) { - buf, err := io.ReadAll(r) + buf, err := readSpecialFile(r) if err != nil { return nil, err } @@ -828,6 +828,16 @@ func tryReadFull(r io.Reader, b []byte) (n int, err error) { return n, err } +// readSpecialFile is like io.ReadAll except it returns +// ErrFieldTooLong if more than maxSpecialFileSize is read. +func readSpecialFile(r io.Reader) ([]byte, error) { + buf, err := io.ReadAll(io.LimitReader(r, maxSpecialFileSize+1)) + if len(buf) > maxSpecialFileSize { + return nil, ErrFieldTooLong + } + return buf, err +} + // discard skips n bytes in r, reporting an error if unable to do so. func discard(r io.Reader, n int64) error { // If possible, Seek to the last byte before the end of the data section. |