diff --git a/lib/libc/sys/read.2 b/lib/libc/sys/read.2
index 994190c075e3..8dd7731a1935 100644
--- a/lib/libc/sys/read.2
+++ b/lib/libc/sys/read.2
@@ -180,6 +180,11 @@ is before the end-of-file, and
 .Fa offset
 is greater than or equal to the offset maximum established
 for this file system.
+.It Bq Er EINVAL
+The value
+.Fa nbytes
+is greater than
+.Dv INT_MAX .
 .El
 .Pp
 In addition,
diff --git a/lib/libc/sys/write.2 b/lib/libc/sys/write.2
index 19b5ce2dea36..7a7cd799bd54 100644
--- a/lib/libc/sys/write.2
+++ b/lib/libc/sys/write.2
@@ -192,6 +192,11 @@ Use
 .Xr disklabel 8
 .Fl W
 to enable writing on the disk label area.
+.It Bq Er EINVAL
+The value
+.Fa nbytes
+is greater than
+.Dv INT_MAX .
 .El
 .Pp
 In addition,