From 3c773cad57064c23873f286fbec69f6f0305b889 Mon Sep 17 00:00:00 2001
From: Martin Matuska <mm@FreeBSD.org>
Date: Sun, 19 Nov 2023 02:09:34 +0100
Subject: [PATCH] cat: fallback on EISDIR with copy_file_range(2)

The filesystem may support reading directories directly
when security.bsd.allow_read_dir is set.

MFC after:	1 week
PR:		275099
---
 bin/cat/cat.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/bin/cat/cat.c b/bin/cat/cat.c
index ce7a83d59d5a6..c69bbc4911cb1 100644
--- a/bin/cat/cat.c
+++ b/bin/cat/cat.c
@@ -281,7 +281,8 @@ scanfiles(char *argv[], int cooked __unused)
 		} else {
 #ifndef BOOTSTRAP_CAT
 			if (in_kernel_copy(fd) == -1) {
-				if (errno == EINVAL || errno == EBADF)
+				if (errno == EINVAL || errno == EBADF ||
+				    errno == EISDIR)
 					raw_cat(fd);
 				else
 					err(1, "stdout");