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 98147C433E6 for ; Thu, 25 Mar 2021 11:27:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6AC5061A61 for ; Thu, 25 Mar 2021 11:27:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231208AbhCYL0h (ORCPT ); Thu, 25 Mar 2021 07:26:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:34248 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230366AbhCYLZy (ORCPT ); Thu, 25 Mar 2021 07:25:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 54FD761A35; Thu, 25 Mar 2021 11:25:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671554; bh=Mm3ZFQ2BMZXi56HpLke80635/E7qUUP52zUhZntN/0U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h1gFMBn5MyHSb5PTB+2Pq71jJzdvB1SNK69wy6/3KrLPzVww09Rf3kfCHOapCKm8X UTorLDmtbEqW1aZzRaiPc0b0k8wvUyIMestUPnumqJet1PqjVuV1eyummBV9j5ujgF DrBflZGcDAoz889WedCHDiy2Umu8KrbtfMraKUkYJEJWQp6cDp+rKZN2WX6J6XUdZO 2uf+zUSGqyZtRHFyz4ozFbWOvYA0nEs0ykXMmuWgLr3zCNwgNbfX+rFgNqZcGy6IFH JsK3YPmw7y6HV/FAqRVtr67zxTwxNIwLILSIL6+o/5Y7lTh1tRgrY9A9W28yKgSB5N /pRzxEdR2NcUA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jens Axboe , Stefan Metzmacher , Sasha Levin Subject: [PATCH AUTOSEL 5.11 42/44] signal: don't allow sending any signals to PF_IO_WORKER threads Date: Thu, 25 Mar 2021 07:24:57 -0400 Message-Id: <20210325112459.1926846-42-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112459.1926846-1-sashal@kernel.org> References: <20210325112459.1926846-1-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 5ad8566534e7..55526b941011 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