1 files changed, 11 insertions, 3 deletions
diff --git a/src/legacy/cuserid.c b/src/legacy/cuserid.c
index 4e78798d..dcaf73d4 100644
--- a/src/legacy/cuserid.c
+++ b/src/legacy/cuserid.c
@@ -2,13 +2,21 @@
 #include <pwd.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <string.h>
 
 char *cuserid(char *buf)
 {
+	static char usridbuf[L_cuserid];
 	struct passwd pw, *ppw;
 	long pwb[256];
-	if (getpwuid_r(geteuid(), &pw, (void *)pwb, sizeof pwb, &ppw))
-		return 0;
-	snprintf(buf, L_cuserid, "%s", pw.pw_name);
+	if (buf) *buf = 0;
+	getpwuid_r(geteuid(), &pw, (void *)pwb, sizeof pwb, &ppw);
+	if (!ppw)
+		return buf;
+	size_t len = strnlen(pw.pw_name, L_cuserid);
+	if (len == L_cuserid)
+		return buf;
+	if (!buf) buf = usridbuf;
+	memcpy(buf, pw.pw_name, len+1);
 	return buf;
 }