From e702f392959d1c2ad2089e595b52235ed97b4e18 Mon Sep 17 00:00:00 2001

From: Kinga Tanska <kinga.tanska@intel.com>

Date: Mon, 6 Jun 2022 12:32:12 +0200

Subject: [PATCH 16/83] Mdmonitor: Fix segfault

Mdadm with "--monitor" parameter requires md device

as an argument to be monitored. If given argument is

not a md device, error shall be returned. Previously

it was not checked and invalid argument caused

segmentation fault. This commit adds checking

that devices passed to mdmonitor are md devices.

Signed-off-by: Kinga Tanska <kinga.tanska@intel.com>

Signed-off-by: Jes Sorensen <jsorensen@fb.com>

---

 Monitor.c | 10 +++++++++-

 mdadm.h   |  1 +

 mdopen.c  | 17 +++++++++++++++++

 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/Monitor.c b/Monitor.c

index c0ab5412..4e5802b5 100644

--- a/Monitor.c

+++ b/Monitor.c

@@ -182,6 +182,7 @@ int Monitor(struct mddev_dev *devlist,

 				continue;

 			if (strcasecmp(mdlist->devname, "<ignore>") == 0)

 				continue;

+

 			st = xcalloc(1, sizeof *st);

 			if (mdlist->devname[0] == '/')

 				st->devname = xstrdup(mdlist->devname);

@@ -190,6 +191,8 @@ int Monitor(struct mddev_dev *devlist,

 				strcpy(strcpy(st->devname, "/dev/md/"),

 				       mdlist->devname);

 			}

+			if (!is_mddev(mdlist->devname))

+				return 1;

 			st->next = statelist;

 			st->devnm[0] = 0;

 			st->percent = RESYNC_UNKNOWN;

@@ -203,7 +206,12 @@ int Monitor(struct mddev_dev *devlist,

 		struct mddev_dev *dv;

 		for (dv = devlist; dv; dv = dv->next) {

-			struct state *st = xcalloc(1, sizeof *st);

+			struct state *st;

+

+			if (!is_mddev(dv->devname))

+				return 1;

+

+			st = xcalloc(1, sizeof *st);

 			mdlist = conf_get_ident(dv->devname);

 			st->devname = xstrdup(dv->devname);

 			st->next = statelist;

diff --git a/mdadm.h b/mdadm.h

index 09915a00..d53df169 100644

--- a/mdadm.h

+++ b/mdadm.h

@@ -1636,6 +1636,7 @@ extern int create_mddev(char *dev, char *name, int autof, int trustworthy,

 #define	FOREIGN	2

 #define	METADATA 3

 extern int open_mddev(char *dev, int report_errors);

+extern int is_mddev(char *dev);

 extern int open_container(int fd);

 extern int metadata_container_matches(char *metadata, char *devnm);

 extern int metadata_subdev_matches(char *metadata, char *devnm);

diff --git a/mdopen.c b/mdopen.c

index 245be537..d18c9319 100644

--- a/mdopen.c

+++ b/mdopen.c

@@ -475,6 +475,23 @@ int open_mddev(char *dev, int report_errors)

 	return mdfd;

 }

+/**

+ * is_mddev() - check that file name passed is an md device.

+ * @dev: file name that has to be checked.

+ * Return: 1 if file passed is an md device, 0 if not.

+ */

+int is_mddev(char *dev)

+{

+	int fd = open_mddev(dev, 1);

+

+	if (fd >= 0) {

+		close(fd);

+		return 1;

+	}

+

+	return 0;

+}

+

 char *find_free_devnm(int use_partitions)

 {

 	static char devnm[32];

-- 

2.38.1