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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 57F42C43142 for ; Fri, 5 Mar 2021 12:41:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A0496502F for ; Fri, 5 Mar 2021 12:41:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233495AbhCEMlo (ORCPT ); Fri, 5 Mar 2021 07:41:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:57116 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233406AbhCEMlL (ORCPT ); Fri, 5 Mar 2021 07:41:11 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id A11A165022; Fri, 5 Mar 2021 12:41:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614948071; bh=PeWfzulb+clhPBVEu08GBvUVQyZF5shtRru7TSyQ4/0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ObHuKLCkXvAqETFS5LS9ErBeYtpYx4QUk+nNnjTy1ogrDid03VjaSqC4pJ3D4R2IL 1kQiDmJXsVT2vMkbEuiR0wmr+nRCJcHyOF0px6nSfLmuZNt/Rn83rnQ+dzdbIbIDK9 no9ahAyW/ppvCGzsVdKRZH0rJJ9Q8oNiy/OQViZI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Dan Carpenter , Thomas Gleixner , "Peter Zijlstra (Intel)" , Ben Hutchings Subject: [PATCH 4.9 07/41] futex: Dont enable IRQs unconditionally in put_pi_state() Date: Fri, 5 Mar 2021 13:22:14 +0100 Message-Id: <20210305120851.638890063@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210305120851.255002428@linuxfoundation.org> References: <20210305120851.255002428@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ben Hutchings From: Dan Carpenter commit 1e106aa3509b86738769775969822ffc1ec21bf4 upstream. The exit_pi_state_list() function calls put_pi_state() with IRQs disabled and is not expecting that IRQs will be enabled inside the function. Use the _irqsave() variant so that IRQs are restored to the original state instead of being enabled unconditionally. Fixes: 153fbd1226fb ("futex: Fix more put_pi_state() vs. exit_pi_state_list() races") Signed-off-by: Dan Carpenter Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201106085205.GA1159983@mwanda Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- kernel/futex.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -882,10 +882,12 @@ static void put_pi_state(struct futex_pi * and has cleaned up the pi_state already */ if (pi_state->owner) { - raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); + unsigned long flags; + + raw_spin_lock_irqsave(&pi_state->pi_mutex.wait_lock, flags); pi_state_update_owner(pi_state, NULL); rt_mutex_proxy_unlock(&pi_state->pi_mutex); - raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); + raw_spin_unlock_irqrestore(&pi_state->pi_mutex.wait_lock, flags); } if (current->pi_state_cache) {