openwrt/package/system/procd/patches/0001-early-keep-stdio-files-open.patch

From 13ebb50d2789de7bd47cebe57e3f6eba58fdcc7e Mon Sep 17 00:00:00 2001
From: Gabor Juhos <[email protected]>
Date: Fri, 19 Jul 2013 08:43:35 +0200
Subject: [PATCH 1/2] early: keep stdio files open

At the end of the 'early_console' function, the
file descriptor is closed unconditionally. This
'close' call closes the stdio files if the fd
returned by the 'open(dev/console)' call equals
with any of the STD{IN,OUT,ERR}_FILENO values.
When this happens, all subsequent accesses to
the stdio files will fail and early console
access won't work.

To avoid this, don't close the file descriptor if
that equals with any of the STD*_FILENO values.

Signed-off-by: Gabor Juhos <[email protected]>
---
Note:

The issue happens if Linux is unable to open the
initial console before calling init. In this case,
the 'open(dev/console)' call in the 'early_console'
function returns with zero.
---
 early.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/early.c b/early.c
index 27d0929..204623b 100644
--- a/early.c
+++ b/early.c
@@ -65,7 +65,11 @@ static void early_console(const char *dev)
 	dup2(dd, STDIN_FILENO);
 	dup2(dd, STDOUT_FILENO);
 	dup2(dd, STDERR_FILENO);
-	close(dd);
+
+	if (dd != STDIN_FILENO &&
+	    dd != STDOUT_FILENO &&
+	    dd != STDERR_FILENO)
+		close(dd);
 }
 
 static void early_env(void)
-- 
1.7.10