[PATCH v2 0/1] MR8404: include: Make sure to null terminate string in wine_dbg_vsprintf.

[Yuxuan Shui (＠yshui)]

vsnprintf isn't always guaranteed to null terminate its output, depends on the
version of msvcrt used.

See !8256 for more information.

supersedes !8256

--
  v2: include: Make sure to null terminate string in wine_dbg_vsprintf.
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/8404

[PATCH v2 1/1] include: Make sure to null terminate string in wine_dbg_vsprintf.

[Yuxuan Shui]

From: Yuxuan Shui <yshui(a)codeweavers.com>

vsnprintf isn't always guaranteed to null terminate its output, depends on the
version of msvcrt used.

See !8256 for more information.
---
 include/wine/debug.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/wine/debug.h b/include/wine/debug.h
index 3e0912de801..17b24b65cfc 100644
--- a/include/wine/debug.h
+++ b/include/wine/debug.h
@@ -133,8 +133,8 @@ static const char * __wine_dbg_cdecl wine_dbg_vsprintf( const char *format, va_l
 static inline const char * __wine_dbg_cdecl wine_dbg_vsprintf( const char *format, va_list args )
 {
     char buffer[200];
-
-    vsnprintf( buffer, sizeof(buffer), format, args );
+    int len = vsnprintf( buffer, sizeof(buffer), format, args );
+    if (len >= sizeof(buffer)) buffer[sizeof(buffer) - 1] = 0;
     return __wine_dbg_strdup( buffer );
 }
 
@@ -154,8 +154,8 @@ static int __wine_dbg_cdecl wine_dbg_vprintf( const char *format, va_list args )
 static inline int __wine_dbg_cdecl wine_dbg_vprintf( const char *format, va_list args )
 {
     char buffer[1024];
-
-    vsnprintf( buffer, sizeof(buffer), format, args );
+    int len = vsnprintf( buffer, sizeof(buffer), format, args );
+    if (len >= sizeof(buffer)) buffer[sizeof(buffer) - 1] = 0;
     return __wine_dbg_output( buffer );
 }
 
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/8404