common: fix bad formatting for DNS-type wireaddr.

rustyrussell · rustyrussell · commit 103cd1c41218 · 2025-11-14T11:50:16.000+10:30
Found by @Chand-ra fuzzing test! Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/common/wireaddr.c b/common/wireaddr.c
@@ -262,7 +262,7 @@ char *fmt_wireaddr_without_port(const tal_t * ctx, const struct wireaddr *a)
 		return tal_fmt(ctx, "%s.onion",
 			       b32_encode(tmpctx, a->addr, a->addrlen));
 	case ADDR_TYPE_DNS:
-		return tal_fmt(ctx, "%s", a->addr);
+		return tal_fmt(ctx, "%.*s", a->addrlen, a->addr);
 	}
 
 	hex = tal_hexstr(ctx, a->addr, a->addrlen);

Original file line number	Diff line number	Diff line change
`@@ -262,7 +262,7 @@ char fmt_wireaddr_without_port(const tal_t ctx, const struct wireaddr *a)`
`262`	`262`	`return tal_fmt(ctx, "%s.onion",`
`263`	`263`	`b32_encode(tmpctx, a->addr, a->addrlen));`
`264`	`264`	`case ADDR_TYPE_DNS:`
`265`		`- return tal_fmt(ctx, "%s", a->addr);`
	`265`	`+ return tal_fmt(ctx, "%.*s", a->addrlen, a->addr);`
`266`	`266`	`}`
`267`	`267`
`268`	`268`	`hex = tal_hexstr(ctx, a->addr, a->addrlen);`