kumquat-buildroot/package/qpdf/0002-Fix-some-pipelines-to-be-safe-if-downstream-write-fails.patch
Fabrice Fontaine 96865f02d4 package/qpdf: fix CVE-2021-36978
QPDF 9.x through 9.1.1 and 10.x through 10.0.4 has a heap-based buffer
overflow in Pl_ASCII85Decoder::write (called from Pl_AES_PDF::flush and
Pl_AES_PDF::finish) when a certain downstream write fails.

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
2021-08-05 21:06:29 +02:00

87 lines
2.6 KiB
Diff

From dc92574c10f3e2516ec6445b88c5d584f40df4e5 Mon Sep 17 00:00:00 2001
From: Jay Berkenbilt <ejb@ql.org>
Date: Mon, 4 Jan 2021 11:55:28 -0500
Subject: [PATCH] Fix some pipelines to be safe if downstream write fails (fuzz
issue 28262)
[Retrieved (and updated to remove updates on ChangeLog and fuzz) from:
https://github.com/qpdf/qpdf/commit/dc92574c10f3e2516ec6445b88c5d584f40df4e5]
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
---
ChangeLog | 6 ++++++
fuzz/qpdf_extra/28262.fuzz | Bin 0 -> 40395 bytes
libqpdf/Pl_AES_PDF.cc | 2 +-
libqpdf/Pl_ASCII85Decoder.cc | 7 +++++--
libqpdf/Pl_ASCIIHexDecoder.cc | 6 ++++--
libqpdf/Pl_Count.cc | 2 +-
6 files changed, 17 insertions(+), 6 deletions(-)
create mode 100644 fuzz/qpdf_extra/28262.fuzz
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);
}
}