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 21303C6FD1D for ; Thu, 30 Mar 2023 13:38:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231397AbjC3Nio (ORCPT ); Thu, 30 Mar 2023 09:38:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229966AbjC3Nil (ORCPT ); Thu, 30 Mar 2023 09:38:41 -0400 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9ECCDB44C; Thu, 30 Mar 2023 06:38:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1680183504; bh=24hs/GAOgBlVSR4B3MD3Qa1OeM+tlMUGandZTll4v9o=; h=From:To:Cc:Subject:Date:From; b=P4hVo2EZZRdByxjRo59jz0QLN9PDmvFRp1opXBJvMaYkvg2EASQ9fPugdPpcXsu2g LOhcUyR2joIXhVYMOdYsHnPIav9cWlqmrlCblMZsHRbJYibESdYmYRvnaRjADKiqm5 j0zdo2Dfqi06FIVg6EH6dYNbEuAj2JMMbpnSVlA+RdMWr8f/BudEMQvMNsMMSwnwZA CPQFJNB/IBo7aYkNiOJskGnM2Vqdqdvd3IjhFyE5TRZ0pKI0KBZhKf2zlNkXwpr/3E UEb7ynurlSL8qN/y3zJcu43QACN215cPl2d/UcsZfRnBrhjoR3E7rV7enw90eVURDy ISZ5k5GBWUw0Q== Received: from localhost.localdomain (192-222-143-198.qc.cable.ebox.net [192.222.143.198]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4PnPdD01kRztMX; Thu, 30 Mar 2023 09:38:23 -0400 (EDT) From: Mathieu Desnoyers To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Shakeel Butt , Marek Szyprowski , linux-mm@kvack.org, stable@vger.kernel.org Subject: [PATCH 1/1] mm: Fix memory leak on mm_init error handling Date: Thu, 30 Mar 2023 09:38:22 -0400 Message-Id: <20230330133822.66271-1-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org commit f1a7941243c1 ("mm: convert mm's rss stats into percpu_counter") introduces a memory leak by missing a call to destroy_context() when a percpu_counter fails to allocate. Before introducing the per-cpu counter allocations, init_new_context() was the last call that could fail in mm_init(), and thus there was no need to ever invoke destroy_context() in the error paths. Adding the following percpu counter allocations adds error paths after init_new_context(), which means its associated destroy_context() needs to be called when percpu counters fail to allocate. Signed-off-by: Mathieu Desnoyers Cc: Shakeel Butt Cc: Andrew Morton Cc: Marek Szyprowski Cc: linux-mm@kvack.org Cc: stable@vger.kernel.org # 6.2 --- kernel/fork.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/fork.c b/kernel/fork.c index c0257cbee093..c983c4fe3090 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1171,6 +1171,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, fail_pcpu: while (i > 0) percpu_counter_destroy(&mm->rss_stat[--i]); + destroy_context(mm); fail_nocontext: mm_free_pgd(mm); fail_nopgd: -- 2.25.1