From patchwork Tue Aug 3 10:59:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 12415913 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=-16.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 D0942C4338F for ; Tue, 3 Aug 2021 10:59:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B85D361040 for ; Tue, 3 Aug 2021 10:59:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235495AbhHCLAF (ORCPT ); Tue, 3 Aug 2021 07:00:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:26703 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235398AbhHCLAF (ORCPT ); Tue, 3 Aug 2021 07:00:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1627988393; 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: in-reply-to:in-reply-to:references:references; bh=X3iQKu65eSqhTXq9sE5TsnnrxJkbiW7EY/s4Ku6sw54=; b=emEjSfcfb/8oc65VnBQFjgnsqs45hG8VlaESEdd8bR97nOGjEJMfe5G+wQutYZVUbVT8Xk hJe/MWeSfErkfdDrgxIdQYQsgp76AiE92ccKXAE+oVYa3BG3FUTfUCxMclOsJClpfcV0AL faxBEZ7kxu0fPWD1382MpBRI4qSEZwE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-131-7iMcmDg-Om-quHLQcVjx-w-1; Tue, 03 Aug 2021 06:59:52 -0400 X-MC-Unique: 7iMcmDg-Om-quHLQcVjx-w-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7A001801AEB; Tue, 3 Aug 2021 10:59:49 +0000 (UTC) Received: from thuth.com (unknown [10.39.192.110]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5A0ED60C05; Tue, 3 Aug 2021 10:59:46 +0000 (UTC) From: Thomas Huth To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org Cc: "J. Bruce Fields" , Chuck Lever , Trond Myklebust , Anna Schumaker , Luis Chamberlain , Kees Cook , Iurii Zaikin , linux-s390@vger.kernel.org, Jia He , Pan Xinhui Subject: [PATCH 1/2] sysctl: introduce new proc handler proc_dobool Date: Tue, 3 Aug 2021 12:59:36 +0200 Message-Id: <20210803105937.52052-2-thuth@redhat.com> In-Reply-To: <20210803105937.52052-1-thuth@redhat.com> References: <20210803105937.52052-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Jia He This is to let bool variable could be correctly displayed in big/little endian sysctl procfs. sizeof(bool) is arch dependent, proc_dobool should work in all arches. Suggested-by: Pan Xinhui Signed-off-by: Jia He [thuth: rebased the patch to the current kernel version] Signed-off-by: Thomas Huth Acked-by: Kees Cook --- include/linux/sysctl.h | 2 ++ kernel/sysctl.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index d99ca99837de..1fa2b69c6fc3 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -48,6 +48,8 @@ typedef int proc_handler(struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos); int proc_dostring(struct ctl_table *, int, void *, size_t *, loff_t *); +int proc_dobool(struct ctl_table *table, int write, void *buffer, + size_t *lenp, loff_t *ppos); int proc_dointvec(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *); int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 272f4a272f8c..25e49b4d8049 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -536,6 +536,21 @@ static void proc_put_char(void **buf, size_t *size, char c) } } +static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp, + int *valp, + int write, void *data) +{ + if (write) { + *(bool *)valp = *lvalp; + } else { + int val = *(bool *)valp; + + *lvalp = (unsigned long)val; + *negp = false; + } + return 0; +} + static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp, int *valp, int write, void *data) @@ -798,6 +813,26 @@ static int do_proc_douintvec(struct ctl_table *table, int write, buffer, lenp, ppos, conv, data); } +/** + * proc_dobool - read/write a bool + * @table: the sysctl table + * @write: %TRUE if this is a write to the sysctl file + * @buffer: the user buffer + * @lenp: the size of the user buffer + * @ppos: file position + * + * Reads/writes up to table->maxlen/sizeof(unsigned int) integer + * values from/to the user buffer, treated as an ASCII string. + * + * Returns 0 on success. + */ +int proc_dobool(struct ctl_table *table, int write, void *buffer, + size_t *lenp, loff_t *ppos) +{ + return do_proc_dointvec(table, write, buffer, lenp, ppos, + do_proc_dobool_conv, NULL); +} + /** * proc_dointvec - read a vector of integers * @table: the sysctl table @@ -1630,6 +1665,12 @@ int proc_dostring(struct ctl_table *table, int write, return -ENOSYS; } +int proc_dobool(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + return -ENOSYS; +} + int proc_dointvec(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { @@ -3425,6 +3466,7 @@ int __init sysctl_init(void) * No sense putting this after each symbol definition, twice, * exception granted :-) */ +EXPORT_SYMBOL(proc_dobool); EXPORT_SYMBOL(proc_dointvec); EXPORT_SYMBOL(proc_douintvec); EXPORT_SYMBOL(proc_dointvec_jiffies);