dm mpath: always free attached_handler_name in parse_path()

Commit b592211c33f7 ("dm mpath: fix attached_handler_name leak and
dangling hw_handler_name pointer") fixed a memory leak for the case
where setup_scsi_dh() returns failure. But setup_scsi_dh may return
success and not "use" attached_handler_name if the
retain_attached_hwhandler flag is not set on the map. As setup_scsi_sh
properly "steals" the pointer by nullifying it, freeing it
unconditionally in parse_path() is safe.

Fixes: b592211c33f7 ("dm mpath: fix attached_handler_name leak and dangling hw_handler_name pointer")
Cc: stable@vger.kernel.org
Reported-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 07cfef67c0bab35fa83d7b1dd0e76b579b2dc334..dbcc1e41cd57dd5a669466a6907a70f78a16014f 100644 (file)
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -897,6 +897,7 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
        if (attached_handler_name || m->hw_handler_name) {
                INIT_DELAYED_WORK(&p->activate_path, activate_path_work);
                r = setup_scsi_dh(p->path.dev->bdev, m, &attached_handler_name, &ti->error);
+               kfree(attached_handler_name);
                if (r) {
                        dm_put_device(ti, p->path.dev);
                        goto bad;
@@ -911,7 +912,6 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
 
        return p;
  bad:
-       kfree(attached_handler_name);
        free_pgpath(p);
        return ERR_PTR(r);
 }