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 X-Spam-Level: X-Spam-Status: No, score=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67C37C433E0 for ; Thu, 25 Mar 2021 11:28:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26C5C61A92 for ; Thu, 25 Mar 2021 11:28:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231273AbhCYL2N (ORCPT ); Thu, 25 Mar 2021 07:28:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:35302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231284AbhCYL0r (ORCPT ); Thu, 25 Mar 2021 07:26:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B2C9661A37; Thu, 25 Mar 2021 11:26:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671607; bh=Fn+7n/epq8bT6dV8fGf7vbv/be+VA2frF0OvHBHiXOQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z4TOO5BJTomRf7LkIz0dm7xENeubulwztOYEprmDMLvRRH60c9h+g4BZxbRTir0Xb u9cYjoJdHcQpyT0XeJ79jAeNT1V0iECkQCW3Oc1dEM8yeHmoyakVrQBOSn1VIgOEjZ VN5n8VYfMQCKcCIcmI5ngO71HmtxBMwXh4zzexVpL0jPhrVRb9kOXQ8BQw4I+ZCZsU +h3knUe1woYH9ezE2Rf3EfkWEEsSKdlbSrpGyVUDaH0c8DaNSKiGgvuV6/qzai55iB uAP0YPqUviDb82E5s64AvNMRIIMq/10q4XqL3ZLLjFEafpUF58bIckXDJ0SUncKd9D k5NVysd1HD2oQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jens Axboe , Stefan Metzmacher , Sasha Levin Subject: [PATCH AUTOSEL 5.10 37/39] signal: don't allow sending any signals to PF_IO_WORKER threads Date: Thu, 25 Mar 2021 07:25:56 -0400 Message-Id: <20210325112558.1927423-37-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112558.1927423-1-sashal@kernel.org> References: <20210325112558.1927423-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jens Axboe [ Upstream commit 5be28c8f85ce99ed2d329d2ad8bdd18ea19473a5 ] They don't take signals individually, and even if they share signals with the parent task, don't allow them to be delivered through the worker thread. Linux does allow this kind of behavior for regular threads, but it's really a compatability thing that we need not care about for the IO threads. Reported-by: Stefan Metzmacher Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- kernel/signal.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/signal.c b/kernel/signal.c index ef8f2a28d37c..18ed1f853439 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -833,6 +833,9 @@ static int check_kill_permission(int sig, struct kernel_siginfo *info, if (!valid_signal(sig)) return -EINVAL; + /* PF_IO_WORKER threads don't take any signals */ + if (t->flags & PF_IO_WORKER) + return -ESRCH; if (!si_fromuser(info)) return 0; -- 2.30.1