Index: share/man/man9/getsn.9
===================================================================
RCS file: /cvs/src/share/man/man9/getsn.9,v
retrieving revision 1.1
diff -u -p -r1.1 getsn.9
--- share/man/man9/getsn.9	23 Apr 2018 10:30:39 -0000	1.1
+++ share/man/man9/getsn.9	23 Apr 2018 10:44:39 -0000
@@ -32,8 +32,8 @@
 .Nd read user input from the console
 .Sh SYNOPSIS
 .In lib/libkern/libkern.h
-.Ft int
-.Fn getsn "char *cp" "int size"
+.Ft size_t
+.Fn getsn "char *cp" "size_t size"
 .Sh DESCRIPTION
 The
 .Fn getsn
Index: sys/lib/libkern/getsn.c
===================================================================
RCS file: /cvs/src/sys/lib/libkern/getsn.c,v
retrieving revision 1.6
diff -u -p -r1.6 getsn.c
--- sys/lib/libkern/getsn.c	5 Dec 2012 23:20:22 -0000	1.6
+++ sys/lib/libkern/getsn.c	23 Apr 2018 10:44:39 -0000
@@ -29,10 +29,11 @@
 #include <sys/systm.h>
 #include <dev/cons.h>
 
-int
-getsn(char *cp, int size)
+size_t
+getsn(char *cp, size_t size)
 {
-	int len = 0, c;
+	size_t len = 0;
+	int  c;
 	char *lp = cp;
 
 	while (1) {
Index: sys/lib/libkern/libkern.h
===================================================================
RCS file: /cvs/src/sys/lib/libkern/libkern.h,v
retrieving revision 1.34
diff -u -p -r1.34 libkern.h
--- sys/lib/libkern/libkern.h	13 Jul 2014 23:49:40 -0000	1.34
+++ sys/lib/libkern/libkern.h	23 Apr 2018 10:44:39 -0000
@@ -183,7 +183,8 @@ size_t	 strlcat(char *, const char *, si
 int	 strcmp(const char *, const char *);
 int	 strncmp(const char *, const char *, size_t);
 int	 strncasecmp(const char *, const char *, size_t);
-int	 getsn(char *, int);
+size_t	 getsn(char *, size_t)
+		__attribute__ ((__bounded__(__string__,1,2)));
 char	*strchr(const char *, int);
 char	*strrchr(const char *, int);
 int	 timingsafe_bcmp(const void *, const void *, size_t);