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=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 E091CC4338F for ; Tue, 17 Aug 2021 20:14:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C557261053 for ; Tue, 17 Aug 2021 20:14:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234761AbhHQUO4 (ORCPT ); Tue, 17 Aug 2021 16:14:56 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:34608 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233690AbhHQUOg (ORCPT ); Tue, 17 Aug 2021 16:14:36 -0400 Date: Tue, 17 Aug 2021 20:14:01 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1629231241; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1dao5T16kInzYwpt2yv7oIhQKw6C2zbPKM5v5aQx8sQ=; b=okTDBHajuht0fZU2iJ0LgwKRWIIqMhGRNJRWupRWZ+XpI8FZIpZL7CKCArt3bvFSX3vNz+ wZJt6kzI4hQsd7Da6SpWnLuwqsJWJxsiF8q/NhyaBe8AMPmI/QQ0q4b40ffe0FABnuwqqT /rrTHzGgtrXLoVXlge3/kz2QuRSkFwTTsrsyvU1ysL9lbhxzKFO3JiOSXeNiY+Bvr6qh+1 caO94XM4MLEOd46YX0B/cuHdNP21esyW9R1wdAqjP6CDtaiOhg+LHznVncJE6zvsZmzEqV v5p62nFn++PUUieOaU1u/oLfOXPqt5IfxMODrM0pzxhw4oJTe4W3xHoG7OMYjg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1629231241; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1dao5T16kInzYwpt2yv7oIhQKw6C2zbPKM5v5aQx8sQ=; b=U1Lm3BlywAXsOf4X9FVyPrtiGUQVUAi99fOAyBEsZWOK/JiwoF3oi0dlbmbKFh7oDT0x3R bH2Zkt2KAkKQpECg== From: "tip-bot2 for Thomas Gleixner" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/core] futex: Reorder sanity checks in futex_requeue() Cc: Davidlohr Bueso , Thomas Gleixner , "Peter Zijlstra (Intel)" , Ingo Molnar , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210815211305.581789253@linutronix.de> References: <20210815211305.581789253@linutronix.de> MIME-Version: 1.0 Message-ID: <162923124113.25758.13783258095447636244.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the locking/core branch of tip: Commit-ID: d69cba5c719b0c551f6380ec5da4ed8c20a3815a Gitweb: https://git.kernel.org/tip/d69cba5c719b0c551f6380ec5da4ed8c20a3815a Author: Thomas Gleixner AuthorDate: Sun, 15 Aug 2021 23:29:15 +02:00 Committer: Ingo Molnar CommitterDate: Tue, 17 Aug 2021 19:05:54 +02:00 futex: Reorder sanity checks in futex_requeue() No point in allocating memory when the input parameters are bogus. Validate all parameters before proceeding. Suggested-by: Davidlohr Bueso Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20210815211305.581789253@linutronix.de --- kernel/futex.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/kernel/futex.c b/kernel/futex.c index 8d8bad5..a5232f6 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1934,13 +1934,6 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags, return -EINVAL; /* - * requeue_pi requires a pi_state, try to allocate it now - * without any locks in case it fails. - */ - if (refill_pi_state_cache()) - return -ENOMEM; - - /* * futex_requeue() allows the caller to define the number * of waiters to wake up via the @nr_wake argument. With * REQUEUE_PI, waking up more than one waiter is creating @@ -1963,6 +1956,13 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags, */ if (nr_wake != 1) return -EINVAL; + + /* + * requeue_pi requires a pi_state, try to allocate it now + * without any locks in case it fails. + */ + if (refill_pi_state_cache()) + return -ENOMEM; } retry: