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 0271FC76196 for ; Tue, 28 Mar 2023 12:01:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232841AbjC1MB5 (ORCPT ); Tue, 28 Mar 2023 08:01:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232598AbjC1MB4 (ORCPT ); Tue, 28 Mar 2023 08:01:56 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B937199 for ; Tue, 28 Mar 2023 05:01:55 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9E5AC616DF for ; Tue, 28 Mar 2023 12:01:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AB7FEC433D2; Tue, 28 Mar 2023 12:01:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680004914; bh=/uYr58Ti2bothrwgGQa8DTx9cwzFBbUjKPmLGjJr+Cw=; h=Subject:To:Cc:From:Date:From; b=bLfJQZmY0oiQlHE/eXJV03bz0TB3xboIY+GNaOdjksmShlj/6pXpSBIzxEnYU6Jww lrgx+V/BMPNqN6cJoPoVg2Sitb9ccJagFTzM6J/LBRRzw6Hr3P546a+QLcFO0xcVyF ymx3GSQnaMboBMeqUwuGi+Z49Edkqd1guf1UqU3c= Subject: FAILED: patch "[PATCH] mm: kfence: fix using kfence_metadata without initialization" failed to apply to 5.15-stable tree To: muchun.song@linux.dev, akpm@linux-foundation.org, dvyukov@google.com, elver@google.com, glider@google.com, jannh@google.com, sjpark@amazon.de, songmuchun@bytedance.com, stable@vger.kernel.org Cc: From: Date: Tue, 28 Mar 2023 14:01:51 +0200 Message-ID: <16800049118459@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 1c86a188e03156223a34d09ce290b49bd4dd0403 # git commit -s git send-email --to '' --in-reply-to '16800049118459@kroah.com' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: 1c86a188e031 ("mm: kfence: fix using kfence_metadata without initialization in show_object()") b33f778bba5e ("kfence: alloc kfence_pool after system startup") 698361bca2d5 ("kfence: allow re-enabling KFENCE after system startup") 07e8481d3c38 ("kfence: always use static branches to guard kfence_alloc()") 08f6b10630f2 ("kfence: limit currently covered allocations when pool nearly full") a9ab52bbcb52 ("kfence: move saving stack trace of allocations into __kfence_alloc()") 9a19aeb56650 ("kfence: count unexpectedly skipped allocations") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 1c86a188e03156223a34d09ce290b49bd4dd0403 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Wed, 15 Mar 2023 11:44:41 +0800 Subject: [PATCH] mm: kfence: fix using kfence_metadata without initialization in show_object() The variable kfence_metadata is initialized in kfence_init_pool(), then, it is not initialized if kfence is disabled after booting. In this case, kfence_metadata will be used (e.g. ->lock and ->state fields) without initialization when reading /sys/kernel/debug/kfence/objects. There will be a warning if you enable CONFIG_DEBUG_SPINLOCK. Fix it by creating debugfs files when necessary. Link: https://lkml.kernel.org/r/20230315034441.44321-1-songmuchun@bytedance.com Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure") Signed-off-by: Muchun Song Tested-by: Marco Elver Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Jann Horn Cc: SeongJae Park Cc: Signed-off-by: Andrew Morton diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 5349c37a5dac..79c94ee55f97 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -726,10 +726,14 @@ static const struct seq_operations objects_sops = { }; DEFINE_SEQ_ATTRIBUTE(objects); -static int __init kfence_debugfs_init(void) +static int kfence_debugfs_init(void) { - struct dentry *kfence_dir = debugfs_create_dir("kfence", NULL); + struct dentry *kfence_dir; + if (!READ_ONCE(kfence_enabled)) + return 0; + + kfence_dir = debugfs_create_dir("kfence", NULL); debugfs_create_file("stats", 0444, kfence_dir, NULL, &stats_fops); debugfs_create_file("objects", 0400, kfence_dir, NULL, &objects_fops); return 0; @@ -883,6 +887,8 @@ static int kfence_init_late(void) } kfence_init_enable(); + kfence_debugfs_init(); + return 0; }