From 283e7ad0241155710f99a9f39d13313a53336926 Mon Sep 17 00:00:00 2001
From: Dan Ehrenberg <dehrenberg@chromium.org>
Date: Tue, 10 Feb 2015 15:20:50 -0800
Subject: [PATCH] init: stricter checking of major:minor root= values
In the kernel command-line, previously, root=1:2jakshflaksjdhfa would
be accepted and interpreted just like root=1:2. This patch adds
stricter checking so that additional characters after major:minor are
rejected by root=.
The goal of this change is to help in unifying DM's interpretation of
its block device argument by using existing kernel code (name_to_dev_t).
But DM rejects malformed major:minor pairs, it seems reasonable for
root= to reject them as well.
Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
init/do_mounts.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/init/do_mounts.c b/init/do_mounts.c
index c16adfbe4ad65..8369ffa5f33db 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -226,8 +226,9 @@ dev_t name_to_dev_t(const char *name)
if (strncmp(name, "/dev/", 5) != 0) {
unsigned maj, min;
+ char dummy;
- if (sscanf(name, "%u:%u", &maj, &min) == 2) {
+ if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2) {
res = MKDEV(maj, min);
if (maj != MAJOR(res) || min != MINOR(res))
goto fail;
--
2.30.2