Subject: Coverity: bch_cached_dev_run(): Memory - illegal accesses

From: coverity-bot <[email-masked]>
Date: Mon, 11 Nov 2019 17:35:10 -0800

Hello!

This is an experimental automated report about issues detected by Coverity
from a scan of next-20191108 as part of the linux-next weekly scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan

You're getting this email because you were associated with the identified
lines of code (noted below) that were touched by recent commits:

ee66850642ef ("bcache: Use bd_link_disk_holder()")

Coverity reported the following:

*** CID 1487848:  Memory - illegal accesses  (USE_AFTER_FREE)
/drivers/md/bcache/super.c: 961 in bch_cached_dev_run()
955     		SET_BDEV_STATE(&dc->sb, BDEV_STATE_STALE);
956     		bch_write_bdev_super(dc, &cl);
957     		closure_sync(&cl);
958     	}
959
960     	add_disk(d->disk);
vvv     CID 1487848:  Memory - illegal accesses  (USE_AFTER_FREE)
vvv     Dereferencing freed pointer "dc".
961     	bd_link_disk_holder(dc->bdev, dc->disk.disk);
962     	/*
963     	 * won't show up in the uevent file, use udevadm monitor -e instead
964     	 * only class / kset properties are persistent
965     	 */
966     	kobject_uevent_env(&disk_to_dev(d->disk)->kobj, KOBJ_CHANGE, env);

If this is a false positive, please let us know so we can mark it as
such, or teach the Coverity rules to be smarter. If not, please make
sure fixes get into linux-next. :) For patches fixing this, please
include these lines (but double-check the "Fixes" first):

Reported-by: coverity-bot <[email-masked]>
Addresses-Coverity-ID: 1487848 ("Memory - illegal accesses")
Fixes: ee66850642ef ("bcache: Use bd_link_disk_holder()")

Thanks for your attention!

-- 
Coverity-bot