[PATCH] monitor: fix nullptr dereference when get_md_name() returns NULL

[Sergey Vidishev]

From f35857936a8df2155b9aee3759c91fc19b77842c Mon Sep 17 00:00:00 2001

From: Sergey Vidishev <***@yandex-team.ru>
Date: Wed, 8 Oct 2014 21:51:03 +0400
Subject: [PATCH] monitor: fix nullptr dereference when get_md_name() returns NULL

Signed-off-by: Sergey Vidishev <***@yandex-team.ru>
---

This patch against fresh git://neil.brown.name/mdadm.
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Monitor.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/Monitor.c b/Monitor.c
index 5cb24fa..1919f99 100644
--- a/Monitor.c
+++ b/Monitor.c
@@ -668,6 +668,7 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist,
{
struct mdstat_ent *mse;
int new_found = 0;
+ char *name;

for (mse=mdstat; mse; mse=mse->next)
if (mse->devnm[0] &&
@@ -678,7 +679,12 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist,
struct state *st = xcalloc(1, sizeof *st);
mdu_array_info_t array;
int fd;
- st->devname = xstrdup(get_md_name(mse->devnm));
+
+ name = get_md_name(mse->devnm);
+ if (!name)
+ return 0;
+
+ st->devname = xstrdup(name);
if ((fd = open(st->devname, O_RDONLY)) < 0 ||
ioctl(fd, GET_ARRAY_INFO, &array)< 0) {
/* no such array */