diff options
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 7287bed6eb64..d413bfaf3527 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -735,7 +735,16 @@ static struct table_device *open_table_device(struct mapped_device *md, return ERR_PTR(-ENOMEM); refcount_set(&td->count, 1); - bdev_file = bdev_file_open_by_dev(dev, mode, _dm_claim_ptr, NULL); + /* + * Open the backing device with kernel rather than caller + * credentials. Otherwise the caller's credentials would be + * pinned in bdev_file->f_cred until the table device is closed. + * That would keep the caller's thread keyring alive long beyond the + * lifetime of the caller, breaking userspace expectation (e.g. + * cryptsetup(8) leaking the LUKS volume key). + */ + scoped_with_kernel_creds() + bdev_file = bdev_file_open_by_dev(dev, mode, _dm_claim_ptr, NULL); if (IS_ERR(bdev_file)) { r = PTR_ERR(bdev_file); goto out_free_td; |