[PATCH iproute 1/3] lib: don't build printf formats out of names

[Stephen Hemminger <stephen@networkplumber.org>]

print_string_name_value() and print_uint_name_value() snprintf'd the
caller's name into a 64-byte buffer and used it as the printf format, so
a '%' in the name was taken as a conversion and names over 63 bytes lost
their value to truncation. Pass the name as a string argument with a
literal format instead.

Fixes: 31ca29b2bec4 ("json_print: Introduce print_#type_name_value")
Reported-by: Anthropic OSS scanner
Assiste-By: Claude:claude-opus-5-5
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/json_print.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/lib/json_print.c b/lib/json_print.c
index f604f265..e028e766 100644
--- a/lib/json_print.c
+++ b/lib/json_print.c
@@ -147,11 +147,8 @@ _PRINT_FUNC(float, double);
 #define _PRINT_NAME_VALUE_FUNC(type_name, type, format_char)		 \
 	void print_##type_name##_name_value(const char *name, type value)\
 	{								 \
-		SPRINT_BUF(format);					 \
-									 \
-		snprintf(format, SPRINT_BSIZE,				 \
-			 "%s %%"#format_char, name);			 \
-		print_##type_name(PRINT_ANY, name, format, value);	 \
+		print_string(PRINT_FP, NULL, "%s ", name);		 \
+		print_##type_name(PRINT_ANY, name, "%"#format_char, value); \
 	}
 _PRINT_NAME_VALUE_FUNC(uint, unsigned int, u);
 _PRINT_NAME_VALUE_FUNC(string, const char*, s);
-- 
2.53.0