Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto fix from Herbert Xu:
 "This fixes a NULL pointer dereference in crypto_remove_spawns that can
  be triggered through af_alg"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: algapi - fix NULL dereference in crypto_remove_spawns()
This commit is contained in:
Linus Torvalds 2018-01-12 09:47:58 -08:00
commit 70cd9071e8

View File

@ -167,6 +167,18 @@ void crypto_remove_spawns(struct crypto_alg *alg, struct list_head *list,
spawn->alg = NULL;
spawns = &inst->alg.cra_users;
/*
* We may encounter an unregistered instance here, since
* an instance's spawns are set up prior to the instance
* being registered. An unregistered instance will have
* NULL ->cra_users.next, since ->cra_users isn't
* properly initialized until registration. But an
* unregistered instance cannot have any users, so treat
* it the same as ->cra_users being empty.
*/
if (spawns->next == NULL)
break;
}
} while ((spawns = crypto_more_spawns(alg, &stack, &top,
&secondary_spawns)));