From 5d55315e32b34af7070d38060ccf9a60941b9696 Mon Sep 17 00:00:00 2001
From: Nick Wellnhofer <[email protected]>
Date: Sat, 18 Feb 2023 17:29:07 +0100
Subject: [PATCH] parser: Fix OOB read when formatting error message

Don't try to print characters beyond the end of the buffer.

Found by OSS-Fuzz.

Reference:https://github.com/GNOME/libxml2/commit/5d55315e32b34af7070d38060ccf9a60941b9696
Conflict:NA
---
 parser.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/parser.c b/parser.c
index 37d7dec..c276a1a 100644
--- a/parser.c
+++ b/parser.c
@@ -12162,7 +12162,11 @@ done:
 #endif
     return(ret);
 encoding_error:
-    {
+    if (ctxt->input->end - ctxt->input->cur < 4) {
+	__xmlErrEncoding(ctxt, XML_ERR_INVALID_CHAR,
+		     "Input is not proper UTF-8, indicate encoding !\n",
+		     NULL, NULL);
+    } else {
         char buffer[150];
 
 	snprintf(buffer, 149, "Bytes: 0x%02X 0x%02X 0x%02X 0x%02X\n",
-- 
2.27.0