From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EFE3EC77B75 for ; Mon, 8 May 2023 09:55:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232273AbjEHJzG (ORCPT ); Mon, 8 May 2023 05:55:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51332 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233637AbjEHJzF (ORCPT ); Mon, 8 May 2023 05:55:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BCA427398 for ; Mon, 8 May 2023 02:55:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2443C6222F for ; Mon, 8 May 2023 09:55:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 212ACC433EF; Mon, 8 May 2023 09:55:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1683539703; bh=bGnXy37wj+1zZwVkd//dszMleNfsUbjCbVnwQOr/H10=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gx3LtoN+r2SL3tQ0scC/qVi/72Q0oynUwROQZ4eHZWMyLabom1MDgFRpa/VP9Q+xX c/a8M0m82fPYfXVStotiC75xwuabHNWK9/0Huq9aHalRx/e83WJBNWsl5awsA1hsoI wYssqeVBM6SiOvSWJ7DE3VjBOElqN0gpS2bBeQIs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Herbert Xu Subject: [PATCH 6.1 069/611] crypto: api - Demote BUG_ON() in crypto_unregister_alg() to a WARN_ON() Date: Mon, 8 May 2023 11:38:31 +0200 Message-Id: <20230508094424.236772771@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230508094421.513073170@linuxfoundation.org> References: <20230508094421.513073170@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Toke Høiland-Jørgensen commit a543ada7db729514ddd3ba4efa45f4c7b802ad85 upstream. The crypto_unregister_alg() function expects callers to ensure that any algorithm that is unregistered has a refcnt of exactly 1, and issues a BUG_ON() if this is not the case. However, there are in fact drivers that will call crypto_unregister_alg() without ensuring that the refcnt has been lowered first, most notably on system shutdown. This causes the BUG_ON() to trigger, which prevents a clean shutdown and hangs the system. To avoid such hangs on shutdown, demote the BUG_ON() in crypto_unregister_alg() to a WARN_ON() with early return. Cc stable because this problem was observed on a 6.2 kernel, cf the link below. Link: https://lore.kernel.org/r/87r0tyq8ph.fsf@toke.dk Cc: stable@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/algapi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/crypto/algapi.c +++ b/crypto/algapi.c @@ -472,7 +472,9 @@ void crypto_unregister_alg(struct crypto if (WARN(ret, "Algorithm %s is not registered", alg->cra_driver_name)) return; - BUG_ON(refcount_read(&alg->cra_refcnt) != 1); + if (WARN_ON(refcount_read(&alg->cra_refcnt) != 1)) + return; + if (alg->cra_destroy) alg->cra_destroy(alg);