diff --git a/ChangeLog b/ChangeLog index 2db53cb8..1e31efb4 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2021-01-04 Jay Berkenbilt + + * Move getNext()->write() calls in some pipelines to ensure that + state gates properly reset even if the next pipeline's write + throws an exception (fuzz issue 28262). + 2021-01-03 Jay Berkenbilt * Don't include -o nospace with zsh completion setup so file diff --git a/fuzz/qpdf_extra/28262.fuzz b/fuzz/qpdf_extra/28262.fuzz new file mode 100644 index 00000000..4e872ba4 Binary files /dev/null and b/fuzz/qpdf_extra/28262.fuzz differ diff --git a/libqpdf/Pl_AES_PDF.cc b/libqpdf/Pl_AES_PDF.cc index 18cf3a4d..2865f804 100644 --- a/libqpdf/Pl_AES_PDF.cc +++ b/libqpdf/Pl_AES_PDF.cc @@ -238,6 +238,6 @@ Pl_AES_PDF::flush(bool strip_padding) } } } - getNext()->write(this->outbuf, bytes); this->offset = 0; + getNext()->write(this->outbuf, bytes); } diff --git a/libqpdf/Pl_ASCII85Decoder.cc b/libqpdf/Pl_ASCII85Decoder.cc index b8df3e87..9d9f6704 100644 --- a/libqpdf/Pl_ASCII85Decoder.cc +++ b/libqpdf/Pl_ASCII85Decoder.cc @@ -119,10 +119,13 @@ Pl_ASCII85Decoder::flush() QTC::TC("libtests", "Pl_ASCII85Decoder partial flush", (this->pos == 5) ? 0 : 1); - getNext()->write(outbuf, this->pos - 1); - + // Reset before calling getNext()->write in case that throws an + // exception. + auto t = this->pos - 1; this->pos = 0; memset(this->inbuf, 117, 5); + + getNext()->write(outbuf, t); } void diff --git a/libqpdf/Pl_ASCIIHexDecoder.cc b/libqpdf/Pl_ASCIIHexDecoder.cc index f20a9769..7845268e 100644 --- a/libqpdf/Pl_ASCIIHexDecoder.cc +++ b/libqpdf/Pl_ASCIIHexDecoder.cc @@ -97,12 +97,14 @@ Pl_ASCIIHexDecoder::flush() QTC::TC("libtests", "Pl_ASCIIHexDecoder partial flush", (this->pos == 2) ? 0 : 1); - getNext()->write(&ch, 1); - + // Reset before calling getNext()->write in case that throws an + // exception. this->pos = 0; this->inbuf[0] = '0'; this->inbuf[1] = '0'; this->inbuf[2] = '\0'; + + getNext()->write(&ch, 1); } void diff --git a/libqpdf/Pl_Count.cc b/libqpdf/Pl_Count.cc index 8077092a..c35619b8 100644 --- a/libqpdf/Pl_Count.cc +++ b/libqpdf/Pl_Count.cc @@ -27,8 +27,8 @@ Pl_Count::write(unsigned char* buf, size_t len) if (len) { this->m->count += QIntC::to_offset(len); - getNext()->write(buf, len); this->m->last_char = buf[len - 1]; + getNext()->write(buf, len); } }