From patchwork Sat Sep 19 04:20:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 309516 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=-9.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 943B7C43464 for ; Sat, 19 Sep 2020 04:20:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 628D82344C for ; Sat, 19 Sep 2020 04:20:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600489223; bh=T16eJfOJMoalDgg9KcTh1y7MMH+8BiJwclfD9iF64J8=; h=Date:From:To:Subject:In-Reply-To:List-ID:From; b=cKj4vSSb5pxp7pQeQmRGD+S0B9CQ8hG+03F8ML4aOykuYaMxWUNW0XJZULeJrGTP5 6DKI4/GM4JBBk7DIAhV9V7+OKRVNFIXa9Yjzlmv4PXQkFoK4clZIcqsMv50fpcFukC P5wEMAMh28CBaxPMrt5S/g5oC5R5YaqwGPlf10C4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726201AbgISEUW (ORCPT ); Sat, 19 Sep 2020 00:20:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:54786 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726009AbgISEUW (ORCPT ); Sat, 19 Sep 2020 00:20:22 -0400 Received: from localhost.localdomain (c-71-198-47-131.hsd1.ca.comcast.net [71.198.47.131]) (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 0BA2220874; Sat, 19 Sep 2020 04:20:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600489222; bh=T16eJfOJMoalDgg9KcTh1y7MMH+8BiJwclfD9iF64J8=; h=Date:From:To:Subject:In-Reply-To:From; b=EggG7EyVJfkMA1ZJBnajXUYRSiukAvNJrve9kosRdMd+ZkF2mkKUWSDMhgNj2VRf1 jedAosI1ey2E1AxpjYh2+p14mj4dFEtXC4dcIl9K34aEStz+AX6+Wm9MuSWxrCtc4Y FQz/GZbGplrzD2MnzP8XzMeTKti0eUqv49zlXEZ0= Date: Fri, 18 Sep 2020 21:20:21 -0700 From: Andrew Morton To: akpm@linux-foundation.org, anil.s.keshavamurthy@intel.com, davem@davemloft.net, linux-mm@kvack.org, mhiramat@kernel.org, mm-commits@vger.kernel.org, naveen.n.rao@linux.ibm.com, rostedt@goodmis.org, songliubraving@fb.com, songmuchun@bytedance.com, stable@vger.kernel.org, torvalds@linux-foundation.org, zhouchengming@bytedance.com Subject: [patch 08/15] kprobes: fix kill kprobe which has been marked as gone Message-ID: <20200919042021.X10NZatlE%akpm@linux-foundation.org> In-Reply-To: <20200918211925.7e97f0ef63d92f5cfe5ccbc5@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Muchun Song Subject: kprobes: fix kill kprobe which has been marked as gone If a kprobe is marked as gone, we should not kill it again. Otherwise, we can disarm the kprobe more than once. In that case, the statistics of kprobe_ftrace_enabled can unbalance which can lead to that kprobe do not work. Link: https://lkml.kernel.org/r/20200822030055.32383-1-songmuchun@bytedance.com Fixes: e8386a0cb22f ("kprobes: support probing module __exit function") Signed-off-by: Muchun Song Co-developed-by: Chengming Zhou Signed-off-by: Chengming Zhou Acked-by: Masami Hiramatsu Cc: "Naveen N . Rao" Cc: Anil S Keshavamurthy Cc: David S. Miller Cc: Song Liu Cc: Steven Rostedt Cc: Signed-off-by: Andrew Morton --- kernel/kprobes.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/kernel/kprobes.c~kprobes-fix-kill-kprobe-which-has-been-marked-as-gone +++ a/kernel/kprobes.c @@ -2140,6 +2140,9 @@ static void kill_kprobe(struct kprobe *p lockdep_assert_held(&kprobe_mutex); + if (WARN_ON_ONCE(kprobe_gone(p))) + return; + p->flags |= KPROBE_FLAG_GONE; if (kprobe_aggrprobe(p)) { /* @@ -2419,7 +2422,10 @@ static int kprobes_module_callback(struc mutex_lock(&kprobe_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; - hlist_for_each_entry(p, head, hlist) + hlist_for_each_entry(p, head, hlist) { + if (kprobe_gone(p)) + continue; + if (within_module_init((unsigned long)p->addr, mod) || (checkcore && within_module_core((unsigned long)p->addr, mod))) { @@ -2436,6 +2442,7 @@ static int kprobes_module_callback(struc */ kill_kprobe(p); } + } } if (val == MODULE_STATE_GOING) remove_module_kprobe_blacklist(mod);