From patchwork Tue Sep 29 11:02:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 263221 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=-10.5 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,USER_AGENT_GIT 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 2C316C4741F for ; Tue, 29 Sep 2020 11:51:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA7B2206A5 for ; Tue, 29 Sep 2020 11:51:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601380261; bh=Jbp3RR9bLIlnoGfpxgRe6jqWokxTH20vJDaI1c7ZaD8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DwmW75t+oedKImL/6Z6TW+QE6Rsl/JSPxmQWm3/AMQRPDwoeez/wETtAGRQogADW2 jOqAqpwf/o77Zg6V2vGjHDDTgIqdeZlXgboTik53PBQKJwypNjMZRG4SI2ayuCuI92 mb+jmox/86ybSedMVHxUnZYlA/B+1tMsvMj0EzZ0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731196AbgI2LtG (ORCPT ); Tue, 29 Sep 2020 07:49:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:52014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731191AbgI2LtD (ORCPT ); Tue, 29 Sep 2020 07:49:03 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 3B0AA206E5; Tue, 29 Sep 2020 11:49:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601380142; bh=Jbp3RR9bLIlnoGfpxgRe6jqWokxTH20vJDaI1c7ZaD8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c4W0EV9m9JFULwozJ2rlLH3ECn2L0Z8xuB5slFCiqpBBUt/n1qXPHYVIyr6b4aj3P 9N/o3xVJFESLmltphOFe9ZAkdmcL0udEXvl+6nwPko8Sxx6ebxY4kcKfa/OVncI5IX ZZUP5THVGocq7XM4ODHXUABMm18CUmGgsvO5qs/w= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jonathan Corbet , Shuah Khan , Randy Dunlap , Ingo Molnar , Masami Hiramatsu , "Steven Rostedt (VMware)" Subject: [PATCH 5.8 85/99] kprobes: tracing/kprobes: Fix to kill kprobes on initmem after boot Date: Tue, 29 Sep 2020 13:02:08 +0200 Message-Id: <20200929105933.919353511@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929105929.719230296@linuxfoundation.org> References: <20200929105929.719230296@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Masami Hiramatsu commit 82d083ab60c3693201c6f5c7a5f23a6ed422098d upstream. Since kprobe_event= cmdline option allows user to put kprobes on the functions in initmem, kprobe has to make such probes gone after boot. Currently the probes on the init functions in modules will be handled by module callback, but the kernel init text isn't handled. Without this, kprobes may access non-exist text area to disable or remove it. Link: https://lkml.kernel.org/r/159972810544.428528.1839307531600646955.stgit@devnote2 Fixes: 970988e19eb0 ("tracing/kprobe: Add kprobe_event= boot parameter") Cc: Jonathan Corbet Cc: Shuah Khan Cc: Randy Dunlap Cc: Ingo Molnar Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- include/linux/kprobes.h | 5 +++++ init/main.c | 2 ++ kernel/kprobes.c | 22 ++++++++++++++++++++++ 3 files changed, 29 insertions(+) --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -369,6 +369,8 @@ void unregister_kretprobes(struct kretpr void kprobe_flush_task(struct task_struct *tk); void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head); +void kprobe_free_init_mem(void); + int disable_kprobe(struct kprobe *kp); int enable_kprobe(struct kprobe *kp); @@ -426,6 +428,9 @@ static inline void unregister_kretprobes static inline void kprobe_flush_task(struct task_struct *tk) { } +static inline void kprobe_free_init_mem(void) +{ +} static inline int disable_kprobe(struct kprobe *kp) { return -ENOSYS; --- a/init/main.c +++ b/init/main.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -1401,6 +1402,7 @@ static int __ref kernel_init(void *unuse kernel_init_freeable(); /* need to finish all async __init code before freeing the memory */ async_synchronize_full(); + kprobe_free_init_mem(); ftrace_free_init_mem(); free_initmem(); mark_readonly(); --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2406,6 +2406,28 @@ static struct notifier_block kprobe_modu extern unsigned long __start_kprobe_blacklist[]; extern unsigned long __stop_kprobe_blacklist[]; +void kprobe_free_init_mem(void) +{ + void *start = (void *)(&__init_begin); + void *end = (void *)(&__init_end); + struct hlist_head *head; + struct kprobe *p; + int i; + + mutex_lock(&kprobe_mutex); + + /* Kill all kprobes on initmem */ + for (i = 0; i < KPROBE_TABLE_SIZE; i++) { + head = &kprobe_table[i]; + hlist_for_each_entry(p, head, hlist) { + if (start <= (void *)p->addr && (void *)p->addr < end) + kill_kprobe(p); + } + } + + mutex_unlock(&kprobe_mutex); +} + static int __init init_kprobes(void) { int i, err = 0;