From 9e6158d274829249322efb3767e6ac2e690cc4a9 Mon Sep 17 00:00:00 2001
From: Eric van Gyzen <vangyzen@FreeBSD.org>
Date: Tue, 6 Apr 2021 09:36:52 -0500
Subject: [PATCH] uefisign: fix handling of errors from child proc

Close the unused pipe file descriptors so the parent will notice if
the child exits prematurely.  Previously, the parent would block
forever on a read from the pipe.

    $ uefisign -c foo.cert -k foo.key -o loader.efi loader.efi.unsigned
    uefisign: section points inside the headers
    load: 0.06  cmd: uefisign 4502 [piperd] 7.25r 0.00u 0.00s 0% 5968k
    ... _sleep+0x1be pipe_read+0x3d6 kern_readv+0x8c sys_read+0x83 ...

Reviewed by:	trasz
MFC after:	1 week
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D29605
---
 usr.sbin/uefisign/uefisign.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/usr.sbin/uefisign/uefisign.c b/usr.sbin/uefisign/uefisign.c
index 149e90ba0e67..7eab934c3394 100644
--- a/usr.sbin/uefisign/uefisign.c
+++ b/usr.sbin/uefisign/uefisign.c
@@ -410,8 +410,12 @@ main(int argc, char **argv)
 	if (pid < 0)
 		err(1, "fork");
 
-	if (pid == 0)
+	if (pid == 0) {
+		close(pipefds[0]);
 		exit(child(inpath, outpath, pipefds[1], Vflag, vflag));
+	}
+
+	close(pipefds[1]);
 
 	if (!Vflag) {
 		certfp = checked_fopen(certpath, "r");