From 9cae1fae6a6d14d4e788b2587b91bf61b26cedfa Mon Sep 17 00:00:00 2001
From: Saleem Abdulrasool <abdulras@thebrowser.company>
Date: Fri, 6 Sep 2024 15:12:54 -0700
Subject: [PATCH] _CFXMLInterface: account for possible `nullptr` return
`xmlSplitQName2` may return `nullptr` for the result, which when passed
to `CFStringCreateWithCString` would attempt to perform
`strlen(nullptr)` which is ill-defined. When updating libxml2 on
Windows, we would perform an invalid memory access due to the `strlen`
invocation inside `CFStringCreateWithCString`. Protect against this
case, returning `NULL` instead.
---
Sources/_CFXMLInterface/CFXMLInterface.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/Sources/_CFXMLInterface/CFXMLInterface.c b/Sources/_CFXMLInterface/CFXMLInterface.c
index 1c54de3ec9..2b86e7f89f 100644
--- a/Sources/_CFXMLInterface/CFXMLInterface.c
+++ b/Sources/_CFXMLInterface/CFXMLInterface.c
@@ -1073,7 +1073,10 @@ CFStringRef _CFXMLNodeCopyPrefix(_CFXMLNodePtr node) {
xmlChar* result = NULL;
xmlChar* unused = xmlSplitQName2(_getQName((xmlNodePtr)node), &result);
- CFStringRef resultString = __CFSwiftXMLParserBridgeCF.CFStringCreateWithCString(NULL, (const char*)result, kCFStringEncodingUTF8);
+ CFStringRef resultString = NULL;
+ if (result) {
+ resultString = __CFSwiftXMLParserBridgeCF.CFStringCreateWithCString(NULL, (const char*)result, kCFStringEncodingUTF8);
+ }
xmlFree(result);
xmlFree(unused);