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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 A305BC433E0 for ; Thu, 11 Feb 2021 02:12:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 679F464DA5 for ; Thu, 11 Feb 2021 02:12:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230005AbhBKCLm (ORCPT ); Wed, 10 Feb 2021 21:11:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:49752 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229999AbhBKCLO (ORCPT ); Wed, 10 Feb 2021 21:11:14 -0500 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 63C6F64ED7; Thu, 11 Feb 2021 02:09:50 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94) (envelope-from ) id 1lA1QT-00BAW9-DS; Wed, 10 Feb 2021 21:09:49 -0500 Message-ID: <20210211020949.299616762@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 10 Feb 2021 21:09:33 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , "Naveen N. Rao" , Ananth N Mavinakayanahalli , Masami Hiramatsu Subject: [for-next][PATCH 06/12] kprobes: Warn if the kprobe is reregistered References: <20210211020927.829775774@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu Warn if the kprobe is reregistered, since there must be a software bug (actively used resource must not be re-registered) and caller must be fixed. Link: https://lkml.kernel.org/r/161236436734.194052.4058506306336814476.stgit@devnote2 Acked-by: Naveen N. Rao Acked-by: Ananth N Mavinakayanahalli Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/kprobes.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index d5a3eb74a657..dd1d027455c4 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1520,13 +1520,16 @@ static struct kprobe *__get_valid_kprobe(struct kprobe *p) return ap; } -/* Return error if the kprobe is being re-registered */ -static inline int check_kprobe_rereg(struct kprobe *p) +/* + * Warn and return error if the kprobe is being re-registered since + * there must be a software bug. + */ +static inline int warn_kprobe_rereg(struct kprobe *p) { int ret = 0; mutex_lock(&kprobe_mutex); - if (__get_valid_kprobe(p)) + if (WARN_ON_ONCE(__get_valid_kprobe(p))) ret = -EINVAL; mutex_unlock(&kprobe_mutex); @@ -1614,7 +1617,7 @@ int register_kprobe(struct kprobe *p) return PTR_ERR(addr); p->addr = addr; - ret = check_kprobe_rereg(p); + ret = warn_kprobe_rereg(p); if (ret) return ret; @@ -1995,7 +1998,7 @@ int register_kretprobe(struct kretprobe *rp) return ret; /* If only rp->kp.addr is specified, check reregistering kprobes */ - if (rp->kp.addr && check_kprobe_rereg(&rp->kp)) + if (rp->kp.addr && warn_kprobe_rereg(&rp->kp)) return -EINVAL; if (kretprobe_blacklist_size) { -- 2.29.2