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 3B110C433EF for ; Thu, 12 May 2022 00:40:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349734AbiELAkL (ORCPT ); Wed, 11 May 2022 20:40:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241922AbiELAkI (ORCPT ); Wed, 11 May 2022 20:40:08 -0400 Received: from out1.migadu.com (out1.migadu.com [91.121.223.63]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 024B8229065 for ; Wed, 11 May 2022 17:40:03 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1652316001; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=/mp8rmMSsisZ3ppz2vovC5V/1mFb0PdJElDJfrKGYrY=; b=MEmmKAOtTHm1X8Bm4ajmG8Sc3JwXYWDwGqKd5TNQ7jBwZSF0kHZ5rr38X/gwGg1rn9O9hB XnhZsayf7Oc7atJdhKxurBG0+0UwYpxfeglIMARujAQ8wE7UWwVrVpW7zzbBfisq1lETEg DSccm17xQE9w91MUU16hq4evPwE6Shk= From: Yajun Deng To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com Cc: linux-kernel@vger.kernel.org, Yajun Deng Subject: [PATCH v2] sched/rt: fix the case where sched_rt_period_us is negative Date: Thu, 12 May 2022 08:39:45 +0800 Message-Id: <20220512003945.610093-1-yajun.deng@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The proc_dointvec() is for integer, but sysctl_sched_rt_period is a unsigned integer, proc_dointvec() would convert negative number into positive number. So both proc_dointvec() and sched_rt_global_validate() aren't return error even if we set a negative number. Use proc_dointvec_minmax() instead of proc_dointvec() and use extra1 limit the minimum value for sched_rt_period_us/sched_rt_runtime_us. Fixes: 391e43da797a ("sched: Move all scheduler bits into kernel/sched/") Signed-off-by: Yajun Deng --- kernel/sched/rt.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index b491a0f8c25d..3add32679885 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -37,6 +37,7 @@ static struct ctl_table sched_rt_sysctls[] = { .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = sched_rt_handler, + .extra1 = SYSCTL_ONE, }, { .procname = "sched_rt_runtime_us", @@ -44,6 +45,8 @@ static struct ctl_table sched_rt_sysctls[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rt_handler, + .extra1 = SYSCTL_NEG_ONE, + .extra2 = (void *)&sysctl_sched_rt_period, }, { .procname = "sched_rr_timeslice_ms", @@ -2959,9 +2962,6 @@ static int sched_rt_global_constraints(void) #ifdef CONFIG_SYSCTL static int sched_rt_global_validate(void) { - if (sysctl_sched_rt_period <= 0) - return -EINVAL; - if ((sysctl_sched_rt_runtime != RUNTIME_INF) && ((sysctl_sched_rt_runtime > sysctl_sched_rt_period) || ((u64)sysctl_sched_rt_runtime * @@ -2992,7 +2992,7 @@ static int sched_rt_handler(struct ctl_table *table, int write, void *buffer, old_period = sysctl_sched_rt_period; old_runtime = sysctl_sched_rt_runtime; - ret = proc_dointvec(table, write, buffer, lenp, ppos); + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (!ret && write) { ret = sched_rt_global_validate(); -- 2.25.1