md: Fix stray --cluster-confirm crash
A --cluster-confirm without an --add (by another node) can
crash the kernel.
Fix it by guarding it using a state.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 03e521a..96679b2 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -42,6 +42,10 @@
__le64 hi;
};
+/* md_cluster_info flags */
+#define MD_CLUSTER_WAITING_FOR_NEWDISK 1
+
+
struct md_cluster_info {
/* dlm lock space and resources for clustered raid. */
dlm_lockspace_t *lockspace;
@@ -61,6 +65,7 @@
struct dlm_lock_resource *no_new_dev_lockres;
struct md_thread *recv_thread;
struct completion newdisk_completion;
+ unsigned long state;
};
enum msg_type {
@@ -380,9 +385,11 @@
snprintf(raid_slot, 16, "RAID_DISK=%d", cmsg->raid_slot);
pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
init_completion(&cinfo->newdisk_completion);
+ set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
kobject_uevent_env(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE, envp);
wait_for_completion_timeout(&cinfo->newdisk_completion,
NEW_DEV_TIMEOUT);
+ clear_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
}
@@ -832,13 +839,19 @@
return ret;
}
-static void new_disk_ack(struct mddev *mddev, bool ack)
+static int new_disk_ack(struct mddev *mddev, bool ack)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
+ if (!test_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state)) {
+ pr_warn("md-cluster(%s): Spurious cluster confirmation\n", mdname(mddev));
+ return -EINVAL;
+ }
+
if (ack)
dlm_unlock_sync(cinfo->no_new_dev_lockres);
complete(&cinfo->newdisk_completion);
+ return 0;
}
static struct md_cluster_operations cluster_ops = {
diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h
index 60d7e58..7417133 100644
--- a/drivers/md/md-cluster.h
+++ b/drivers/md/md-cluster.h
@@ -21,7 +21,7 @@
int (*area_resyncing)(struct mddev *mddev, sector_t lo, sector_t hi);
int (*add_new_disk_start)(struct mddev *mddev, struct md_rdev *rdev);
int (*add_new_disk_finish)(struct mddev *mddev);
- void (*new_disk_ack)(struct mddev *mddev, bool ack);
+ int (*new_disk_ack)(struct mddev *mddev, bool ack);
};
#endif /* _MD_CLUSTER_H */
diff --git a/drivers/md/md.c b/drivers/md/md.c
index ae3432e..eb6f92e 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5755,7 +5755,7 @@
if (mddev_is_clustered(mddev) &&
!(info->state & ((1 << MD_DISK_CLUSTER_ADD) | (1 << MD_DISK_CANDIDATE)))) {
- pr_err("%s: Cannot add to clustered mddev. Try --cluster-add\n",
+ pr_err("%s: Cannot add to clustered mddev.\n",
mdname(mddev));
return -EINVAL;
}
@@ -5853,7 +5853,11 @@
if (info->state & (1 << MD_DISK_CANDIDATE)) {
/* Through --cluster-confirm */
set_bit(Candidate, &rdev->flags);
- md_cluster_ops->new_disk_ack(mddev, true);
+ err = md_cluster_ops->new_disk_ack(mddev, true);
+ if (err) {
+ export_rdev(rdev);
+ return err;
+ }
} else if (info->state & (1 << MD_DISK_CLUSTER_ADD)) {
/* --add initiated by this node */
err = md_cluster_ops->add_new_disk_start(mddev, rdev);