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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDED9C433EF for ; Wed, 1 Dec 2021 14:46:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351185AbhLAOtl (ORCPT ); Wed, 1 Dec 2021 09:49:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351134AbhLAOtU (ORCPT ); Wed, 1 Dec 2021 09:49:20 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1A3DC061748 for ; Wed, 1 Dec 2021 06:45:57 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 03187CE1F4D for ; Wed, 1 Dec 2021 14:45:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ADA4CC53FCD; Wed, 1 Dec 2021 14:45:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638369954; bh=7Ho7n6rjLlleXHreFeiPC12K7HB5s3y00yAbj5K+LLA=; h=From:To:Cc:Subject:Date:From; b=dc4L8v+0e2lPEQm6mm7W/39YbQuH509szTu3Z2qX0lT/dwzp8ATbDXZXpvuaoqgsx U1hlJ2e9JfIO7VNXDEXzNj/wV2Jbf4rCOr3E7hGFNWFK7Vb1GMp/6fjZLFDgsYO+Ge 5gczCOo56neSHvW/1XBSRkNsxmjcpCdkuX30eKYJ5K57VocTyuyLvLUSiv3/T853fK xFZc01JIrjMgeoQp1xDq2h0rQ7lxgqglvda0BYWPRAlumCUny17LJMpT03ddRWmSNy SKYGxCsaMtUD9Z/4xSOHt0Wj0Paako7fdw/PTlPPzOiBSHDy+gaWzOmmaAHF5Ep/mS z4nQksTtaD0pw== From: Masami Hiramatsu To: Steven Rostedt Cc: LKML , zhangyue , naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com, davem@davemloft.net, mhiramat@kernel.org Subject: [PATCH] kprobes: Limit max data_size of the kretprobe instances Date: Wed, 1 Dec 2021 23:45:50 +0900 Message-Id: <163836995040.432120.10322772773821182925.stgit@devnote2> X-Mailer: git-send-email 2.25.1 User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The kretprobe::data_size is unsigned (size_t) but it is used as 'data_size + sizeof(struct kretprobe_instance)'. Thus, it can be smaller than sizeof(struct kretprobe_instance) while allocating memory for the kretprobe_instance. To avoid this issue, introduce a max limitation of the kretprobe::data_size. 4KB per instance should be OK. Reported-by: zhangyue Fixes: f47cd9b553aa ("kprobes: kretprobe user entry-handler") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu --- include/linux/kprobes.h | 2 ++ kernel/kprobes.c | 3 +++ 2 files changed, 5 insertions(+) diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index e974caf39d3e..8c8f7a4d93af 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -153,6 +153,8 @@ struct kretprobe { struct kretprobe_holder *rph; }; +#define KRETPROBE_MAX_DATA_SIZE 4096 + struct kretprobe_instance { union { struct freelist_node freelist; diff --git a/kernel/kprobes.c b/kernel/kprobes.c index e9db0c810554..21eccc961bba 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2086,6 +2086,9 @@ int register_kretprobe(struct kretprobe *rp) } } + if (rp->data_size > KRETPROBE_MAX_DATA_SIZE) + return -E2BIG; + rp->kp.pre_handler = pre_handler_kretprobe; rp->kp.post_handler = NULL;