dm raid: stop using BUG() in __rdev_sectors()

Return 0 rather than BUG() if __rdev_sectors() fails and catch invalid
rdev size in the constructor.

Reported-by: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 7d893228c40f50dd7d0017fca004b504fa27f567..67b3eb23e771854e1dd6514a63ff4471e27e0396 100644 (file)
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -1571,7 +1571,7 @@ static sector_t __rdev_sectors(struct raid_set *rs)
                        return rdev->sectors;
        }
 
-       BUG(); /* Constructor ensures we got some. */
+       return 0;
 }
 
 /* Calculate the sectors per device and per array used for @rs */
@@ -2930,7 +2930,7 @@ static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
        bool resize;
        struct raid_type *rt;
        unsigned int num_raid_params, num_raid_devs;
-       sector_t calculated_dev_sectors;
+       sector_t calculated_dev_sectors, rdev_sectors;
        struct raid_set *rs = NULL;
        const char *arg;
        struct rs_layout rs_layout;
@@ -3006,7 +3006,14 @@ static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
        if (r)
                goto bad;
 
-       resize = calculated_dev_sectors != __rdev_sectors(rs);
+       rdev_sectors = __rdev_sectors(rs);
+       if (!rdev_sectors) {
+               ti->error = "Invalid rdev size";
+               r = -EINVAL;
+               goto bad;
+       }
+
+       resize = calculated_dev_sectors != rdev_sectors;
 
        INIT_WORK(&rs->md.event_work, do_table_event);
        ti->private = rs;