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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 DA293C3A5A2 for ; Sun, 22 Sep 2019 19:03:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B4DB22070C for ; Sun, 22 Sep 2019 19:03:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569179001; bh=vjBaosXqtd9ltgOm7s+SR9vWpf2jQAJtR0eeELBX1YY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jyulRf7zWclgf6crzwJh+ZGEKVBmuwMu8DXYDyoMxe5XJ4LpqhXsoQuKtpaNi4WHJ vEsjZyGVfxj1z7ZMLfH8+QZ6SFPv05VHav1jeqpOa8qsTrjS8JaD9IqbIxRIvIzOS5 A7Rdbq/+EvW/1SPH/4lgB06njMVBMp1QsGZxxzPo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729750AbfIVTDU (ORCPT ); Sun, 22 Sep 2019 15:03:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:38312 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2395359AbfIVTCA (ORCPT ); Sun, 22 Sep 2019 15:02:00 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7F461214AF; Sun, 22 Sep 2019 19:01:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569178919; bh=vjBaosXqtd9ltgOm7s+SR9vWpf2jQAJtR0eeELBX1YY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pfxx35Ark3MQkE4HqTC6It2UBmZlWuPMLrkkCXYCLk3EYeffXXEjAXee06HPhC7pM O717Y5zeunm+4gXMuV72ZDu77N1ggMca0dpJ0a/BF/iJSejeCJGHonNesb65xuj4wR 8MhZax3AQL7fv37S80S9rrGBMa/fxzPyrSfnuC1k= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Masami Hiramatsu , Steven Rostedt , "Naveen N . Rao" , Anil S Keshavamurthy , "David S . Miller" , Linus Torvalds , "Naveen N . Rao" , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL 4.4 36/44] kprobes: Prohibit probing on BUG() and WARN() address Date: Sun, 22 Sep 2019 15:00:54 -0400 Message-Id: <20190922190103.4906-36-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190922190103.4906-1-sashal@kernel.org> References: <20190922190103.4906-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu [ Upstream commit e336b4027775cb458dc713745e526fa1a1996b2a ] Since BUG() and WARN() may use a trap (e.g. UD2 on x86) to get the address where the BUG() has occurred, kprobes can not do single-step out-of-line that instruction. So prohibit probing on such address. Without this fix, if someone put a kprobe on WARN(), the kernel will crash with invalid opcode error instead of outputing warning message, because kernel can not find correct bug address. Signed-off-by: Masami Hiramatsu Acked-by: Steven Rostedt (VMware) Acked-by: Naveen N. Rao Cc: Anil S Keshavamurthy Cc: David S . Miller Cc: Linus Torvalds Cc: Naveen N . Rao Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/156750890133.19112.3393666300746167111.stgit@devnote2 Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- include/linux/bug.h | 5 +++++ kernel/kprobes.c | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/include/linux/bug.h b/include/linux/bug.h index 7f4818673c41f..581a53dfbd310 100644 --- a/include/linux/bug.h +++ b/include/linux/bug.h @@ -102,6 +102,11 @@ int is_valid_bugaddr(unsigned long addr); #else /* !CONFIG_GENERIC_BUG */ +static inline void *find_bug(unsigned long bugaddr) +{ + return NULL; +} + static inline enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs) { diff --git a/kernel/kprobes.c b/kernel/kprobes.c index a53998cba804c..fdde50d39a46d 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1454,7 +1454,8 @@ static int check_kprobe_address_safe(struct kprobe *p, /* Ensure it is not in reserved area nor out of text */ if (!kernel_text_address((unsigned long) p->addr) || within_kprobe_blacklist((unsigned long) p->addr) || - jump_label_text_reserved(p->addr, p->addr)) { + jump_label_text_reserved(p->addr, p->addr) || + find_bug((unsigned long)p->addr)) { ret = -EINVAL; goto out; } -- 2.20.1