From e3b65ab43d2e2d097a4cd2ee5aa1e1606a8a0663 Mon Sep 17 00:00:00 2001 From: Andrei Gherzan Date: Fri, 24 Mar 2017 16:39:08 +0100 Subject: switch_root: don't bail out when console doesn't exist Busybox is very often used in initramfs at the end of which usually there is a switch_root to the actual rootfs. There are many cases where the console kernel argument is either just a placeholder (for example RaspberryPi uses serial0 and serial1) or configured as null to avoid any console messages - usually you would see such of a setup in production environments. Currently busybox bails out if can't open the console argument. If this happenes in initramfs and if the console=null for example, you get in a blind kernel panic. Avoid this by only warning instead of dying. function old new delta switch_root_main 371 368 -3 Signed-off-by: Andrei Gherzan Signed-off-by: Denys Vlasenko --- util-linux/switch_root.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/util-linux/switch_root.c b/util-linux/switch_root.c index 6034485d7..aaee35a3e 100644 --- a/util-linux/switch_root.c +++ b/util-linux/switch_root.c @@ -141,10 +141,12 @@ int switch_root_main(int argc UNUSED_PARAM, char **argv) // If a new console specified, redirect stdin/stdout/stderr to it if (console) { - close(0); - xopen(console, O_RDWR); - xdup2(0, 1); - xdup2(0, 2); + int fd = open_or_warn(console, O_RDWR); + if (fd >= 0) { + xmove_fd(fd, 0); + xdup2(0, 1); + xdup2(0, 2); + } } // Exec real init -- cgit v1.2.3