[master] 9b31fcdcd vsl: Coveritification

[Nils Goroll]

commit 9b31fcdcd6d1638e7f0e4baa3c21567970e0b642
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Tue Jun 3 17:17:44 2025 +0200

    vsl: Coveritification
    
    CID1605309 reports a potential "cast overflow" for  l = VSL_OVERHEAD +
    VSL_WORDS(VSL_LEN(c->buf));
    
    This can not happen because VSL_LEN is limited to UINT16_MAX plus VSL_OVERHEAD
    (3). Hopefully the explicit cast will make this clear.

diff --git a/include/vapi/vsl_int.h b/include/vapi/vsl_int.h
index 87d38b04c..b220a82e3 100644
--- a/include/vapi/vsl_int.h
+++ b/include/vapi/vsl_int.h
@@ -81,14 +81,14 @@
 #define VSL_VERSHIFT		16
 #define VSL_IDMASK		0xff
 #define VSL_IDSHIFT		24
-#define VSL_OVERHEAD		3
+#define VSL_OVERHEAD		3U
 #define VSL_VERSION_2		0x0
 #define VSL_VERSION_3		0x1
 #define VSL_WORDS(len)		(((len) + 3) / 4)
 #define VSL_BYTES(words)	((words) * 4)
 #define VSL_END(ptr, len)	((ptr) + VSL_OVERHEAD + VSL_WORDS(len))
 #define VSL_NEXT(ptr)		VSL_END(ptr, VSL_LEN(ptr))
-#define VSL_LEN(ptr)		((ptr)[0] & VSL_LENMASK)
+#define VSL_LEN(ptr)		((uint16_t)((ptr)[0] & VSL_LENMASK))
 #define VSL_VER(ptr)		(((ptr)[0] >> VSL_VERSHIFT) & VSL_VERMASK)
 #define VSL_TAG(ptr)		((enum VSL_tag_e)((ptr)[0] >> VSL_IDSHIFT))
 #define VSL_ID64(ptr)		(((uint64_t)((ptr)[2])<<32) | ((ptr)[1]))