# HG changeset patch
# User Gregory Szorc <gregory.szorc@gmail.com>
# Date 2017-01-17 18:17:13
# Node ID 08fa3a76a0803cbae15883ee9521fe2dc4eda96d
# Parent  08b34c3a6f74800b5b357f371568177827963e2b

zstd: prevent potential free() of uninitialized memory

This is a cherry pick of an upstream fix. The free() of uninitialed
memory could likely only occur if a malloc() inside zstd fails.

The patched functions aren't currently used by Mercurial. But I don't
like leaving footguns sitting around.

diff --git a/contrib/python-zstandard/c-ext/compressor.c b/contrib/python-zstandard/c-ext/compressor.c
--- a/contrib/python-zstandard/c-ext/compressor.c
+++ b/contrib/python-zstandard/c-ext/compressor.c
@@ -258,6 +258,9 @@ static PyObject* ZstdCompressor_copy_str
 		return NULL;
 	}
 
+	/* Prevent free on uninitialized memory in finally. */
+	output.dst = NULL;
+
 	cstream = CStream_from_ZstdCompressor(self, sourceSize);
 	if (!cstream) {
 		res = NULL;
diff --git a/contrib/python-zstandard/c-ext/decompressor.c b/contrib/python-zstandard/c-ext/decompressor.c
--- a/contrib/python-zstandard/c-ext/decompressor.c
+++ b/contrib/python-zstandard/c-ext/decompressor.c
@@ -165,6 +165,9 @@ static PyObject* Decompressor_copy_strea
 		return NULL;
 	}
 
+	/* Prevent free on uninitialized memory in finally. */
+	output.dst = NULL;
+
 	dstream = DStream_from_ZstdDecompressor(self);
 	if (!dstream) {
 		res = NULL;