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 677FBC433EF for ; Sat, 26 Mar 2022 03:27:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229893AbiCZD2h (ORCPT ); Fri, 25 Mar 2022 23:28:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229773AbiCZD2g (ORCPT ); Fri, 25 Mar 2022 23:28:36 -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 BF4F115E8AB for ; Fri, 25 Mar 2022 20:27:00 -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 59348619E2 for ; Sat, 26 Mar 2022 03:27:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AD097C340F0; Sat, 26 Mar 2022 03:26:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648265219; bh=PS0CGn2EIumYSltpMiWtHcy8WE4ZP4zhpTILnYzh4J4=; h=Date:To:From:Subject:From; b=UMjha3unpJTY/5lL+rZZ9pbEnQe+EwoJMiIe4oAfrbPI2PsuOy21pBRG3Qbq6VQH7 AuoHMLA/u8R79pOK4NqNqAR2apXCDHEjxZD583BY9WtufU+PHrXQDLJQs8g+sF/CXj fZ8ZtY0sY3HGdmUZcAmdEKEbZIIClWPWATdu+g5A= Date: Fri, 25 Mar 2022 20:26:58 -0700 To: mm-commits@vger.kernel.org, viro@zeniv.linux.org.uk, juanfengpy@gmail.com, adobriyan@gmail.com, akpm@linux-foundation.org From: Andrew Morton Subject: + proc-fix-dentry-inode-overinstantiating-under-proc-pid-net.patch added to -mm tree Message-Id: <20220326032659.AD097C340F0@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: proc: fix dentry/inode overinstantiating under /proc/${pid}/net has been added to the -mm tree. Its filename is proc-fix-dentry-inode-overinstantiating-under-proc-pid-net.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/proc-fix-dentry-inode-overinstantiating-under-proc-pid-net.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/proc-fix-dentry-inode-overinstantiating-under-proc-pid-net.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Alexey Dobriyan Subject: proc: fix dentry/inode overinstantiating under /proc/${pid}/net When a process exits, /proc/${pid}, and /proc/${pid}/net dentries are flushed. However some leaf dentries like /proc/${pid}/net/arp_cache aren't. That's because respective PDEs have proc_misc_d_revalidate() hook which returns 1 and leaves dentries/inodes in the LRU. Force revalidation/lookup on everything under /proc/${pid}/net by inheriting proc_net_dentry_ops. Link: https://lkml.kernel.org/r/YjdVHgildbWO7diJ@localhost.localdomain Fixes: c6c75deda813 ("proc: fix lookup in /proc/net subdirectories after setns(2)") Signed-off-by: Alexey Dobriyan Reported-by: hui li Cc: Al Viro Signed-off-by: Andrew Morton --- fs/proc/generic.c | 4 ++++ fs/proc/proc_net.c | 3 +++ 2 files changed, 7 insertions(+) --- a/fs/proc/generic.c~proc-fix-dentry-inode-overinstantiating-under-proc-pid-net +++ a/fs/proc/generic.c @@ -448,6 +448,10 @@ static struct proc_dir_entry *__proc_cre proc_set_user(ent, (*parent)->uid, (*parent)->gid); ent->proc_dops = &proc_misc_dentry_ops; + /* Revalidate everything under /proc/${pid}/net */ + if ((*parent)->proc_dops == &proc_net_dentry_ops) { + pde_force_lookup(ent); + } out: return ent; --- a/fs/proc/proc_net.c~proc-fix-dentry-inode-overinstantiating-under-proc-pid-net +++ a/fs/proc/proc_net.c @@ -376,6 +376,9 @@ static __net_init int proc_net_ns_init(s proc_set_user(netd, uid, gid); + /* Seed dentry revalidation for /proc/${pid}/net */ + pde_force_lookup(netd); + err = -EEXIST; net_statd = proc_net_mkdir(net, "stat", netd); if (!net_statd) _ Patches currently in -mm which might be from adobriyan@gmail.com are proc-fix-dentry-inode-overinstantiating-under-proc-pid-net.patch