On 4/5/22 7:40 PM, Kinga Tanska wrote:
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@xxxxxxxxx>
Signed-off-by: Oleksandr Shchirskyi <oleksandr.shchirskyi@xxxxxxxxx>
---
Monitor.c | 11 ++++++++++-
mdadm.h | 1 +
mdopen.c | 17 +++++++++++++++++
3 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/Monitor.c b/Monitor.c
index f5412299..0b24b656 100644
--- a/Monitor.c
+++ b/Monitor.c
@@ -183,6 +183,10 @@ int Monitor(struct mddev_dev *devlist,
continue;
if (strcasecmp(mdlist->devname, "<ignore>") == 0)
continue;
+
+ if (!is_mddev(mdlist->devname))
+ return 1;
+
st = xcalloc(1, sizeof *st);
if (mdlist->devname[0] == '/')
st->devname = xstrdup(mdlist->devname);
HI Kinga,
Suddenly I realize that your test for the above change might not be
complete.
mdlist->devname is permitted to be a relative path under /dev/md/, with
your change such devname will be regarded as invalid by is_mddev().
Because open_mddev() only takes absolute path. Maybe is_mddev() should
be called several lines behind current location.
The rested part of the patch is fine to me.
Thanks.
Coly Li
@@ -204,7 +208,12 @@ 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 8f8841d8..03151c34 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -1607,6 +1607,7 @@ 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];
