Eduard Permyakov : xmllite: Don't lose terminating character when shrinking buffer.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 2d33f406c93bc0d5c0ec6053a3967a19ee5e9f72
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=2d33f406c93bc0d5c0ec6053a...

Author: Eduard Permyakov 
Date:   Fri Aug  6 15:01:16 2021 +0300

xmllite: Don't lose terminating character when shrinking buffer.

The utf16 buffer is expected to be terminated by a '0' character.
Flawed buffer shrinking logic would move the buffer contents but
forget about the terminating character, which could cause reading
junk past the end of the buffer contents.

Signed-off-by: Eduard Permyakov 
Signed-off-by: Nikolay Sivov 
Signed-off-by: Alexandre Julliard

---

dlls/xmllite/reader.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dlls/xmllite/reader.c b/dlls/xmllite/reader.c
index a5a75c29887..834c36ae18c 100644
--- a/dlls/xmllite/reader.c
+++ b/dlls/xmllite/reader.c
@@ -2128,6 +2128,7 @@ static HRESULT reader_parse_reference(xmlreader *reader)
         memmove(start + 1, ptr + 1, len);

buffer->written -= (reader_get_cur(reader) - cur) * sizeof(WCHAR);
+        *(WCHAR*)(buffer->data + buffer->written) = 0;
         buffer->cur = cur + 1;

*start = ch;
@@ -2151,6 +2152,7 @@ static HRESULT reader_parse_reference(xmlreader *reader)
             memmove(start+1, ptr+1, len);
             buffer->cur = cur + 1;
             buffer->written -= (ptr - start) * sizeof(WCHAR);
+            *(WCHAR*)(buffer->data + buffer->written) = 0;

*start = ch;
         }