From patchwork Tue Sep 29 10:59:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 263387 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=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 03BDCC4727C for ; Tue, 29 Sep 2020 11:07:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A622321D46 for ; Tue, 29 Sep 2020 11:07:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601377653; bh=Wb2GbvW6M0O8nQ8XEZKqP6wgNcnqbhsJbKcF/STvFEg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IQ+8iiLZQfmtUR3WCvDQTidUgdaJI/1oim113+kRdBbpH7cpG4TSH31/NXI2kd9ja wv8PtN3MJ8tdsNQfKFeqkCUZ4uK76WuCvZasHfHYNh5LxYNr+c+zCo5AX4DqPSnrw1 cUm2nw9H96ZtNQqSgsoTMJ8MVWy9PTCX5XcEbYxI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728618AbgI2LHc (ORCPT ); Tue, 29 Sep 2020 07:07:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:45758 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728531AbgI2LHQ (ORCPT ); Tue, 29 Sep 2020 07:07:16 -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 2327221D7D; Tue, 29 Sep 2020 11:07:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601377636; bh=Wb2GbvW6M0O8nQ8XEZKqP6wgNcnqbhsJbKcF/STvFEg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dRZfUJM4mrTwg0k20RIKtD5ieLdi6Hk4/aEkfeDVTHHlASuuH5aAbdZEqNgTOa2X3 nshxEMifWsCfbTnTydUPlfyr85Ah7cpBN66ZZRfd86Rej8OfvPHkVmXo6xpP9VGav7 xjZ3d6tqaM+6FaZYT+Ho4HdrF7/UUec3mDGfo7JA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Muchun Song , Chengming Zhou , Andrew Morton , Masami Hiramatsu , "Naveen N . Rao" , Anil S Keshavamurthy , "David S. Miller" , Song Liu , Steven Rostedt , Linus Torvalds , Sasha Levin Subject: [PATCH 4.9 003/121] kprobes: fix kill kprobe which has been marked as gone Date: Tue, 29 Sep 2020 12:59:07 +0200 Message-Id: <20200929105930.354636159@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929105930.172747117@linuxfoundation.org> References: <20200929105930.172747117@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Muchun Song [ Upstream commit b0399092ccebd9feef68d4ceb8d6219a8c0caa05 ] 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. Fixes: e8386a0cb22f ("kprobes: support probing module __exit function") Co-developed-by: Chengming Zhou Signed-off-by: Muchun Song Signed-off-by: Chengming Zhou Signed-off-by: Andrew Morton Acked-by: Masami Hiramatsu Cc: "Naveen N . Rao" Cc: Anil S Keshavamurthy Cc: David S. Miller Cc: Song Liu Cc: Steven Rostedt Cc: Link: https://lkml.kernel.org/r/20200822030055.32383-1-songmuchun@bytedance.com Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- kernel/kprobes.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 9aa2dbe6a4568..6f63d78aceeca 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2012,6 +2012,9 @@ static void kill_kprobe(struct kprobe *p) { struct kprobe *kp; + if (WARN_ON_ONCE(kprobe_gone(p))) + return; + p->flags |= KPROBE_FLAG_GONE; if (kprobe_aggrprobe(p)) { /* @@ -2154,7 +2157,10 @@ static int kprobes_module_callback(struct notifier_block *nb, mutex_lock(&kprobe_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; - hlist_for_each_entry_rcu(p, head, hlist) + hlist_for_each_entry_rcu(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))) { @@ -2165,6 +2171,7 @@ static int kprobes_module_callback(struct notifier_block *nb, */ kill_kprobe(p); } + } } mutex_unlock(&kprobe_mutex); return NOTIFY_DONE;