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=-13.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 C6C69C43444 for ; Thu, 10 Jan 2019 02:56:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8BED62173B for ; Thu, 10 Jan 2019 02:56:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547088981; bh=7hV26Yvl3TCvwYB6NQ5s6i94lsjT618yvD+wN6GMg6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Lf4K6Ub+k+Pt9HkZ7ufSsmG5Q7ifchX2jvaVfqfXM4sMfEkZ3UzPvrKhvxr+VoYDr IDBc52B++fSB4QB3ZO5XL7FpTzjiJWsPO8C/D0UOmrssvROtB5FIlJCdAiUGjK+6Vw qzGomUiaalJMXQUG6GSmnuehx6PfWiTgMmYOFzdI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727251AbfAJC4U (ORCPT ); Wed, 9 Jan 2019 21:56:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:38754 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726458AbfAJC4U (ORCPT ); Wed, 9 Jan 2019 21:56:20 -0500 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (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 15F0420665; Thu, 10 Jan 2019 02:56:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547088979; bh=7hV26Yvl3TCvwYB6NQ5s6i94lsjT618yvD+wN6GMg6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HbtQV+owD4sd6DrX77CKdvqobKMpculz2bcXR7yp9ptfhdP26mh9XlATV3S91G4Zw fThY1IftscLwjeAthuYe2/xOgUqoaCJ4joT8OVWMsy+Sp5pgxaj1bpu8cnR2myDIlG QcXiqPJA8NATQdEdCydLGFPiiz59EmOEa5HYV830= From: Masami Hiramatsu To: Ingo Molnar Cc: Masami Hiramatsu , peterz@infradead.org, Mathieu Desnoyers , linux-kernel , Andrea Righi , Steven Rostedt , stable@vger.kernel.org Subject: [PATCH 4/9] x86/kprobes: Prohibit probing on IRQ handlers directly Date: Thu, 10 Jan 2019 11:55:56 +0900 Message-Id: <154708895611.6325.16510388138654464604.stgit@devbox> X-Mailer: git-send-email 2.13.6 In-Reply-To: <154708884117.6325.4454464467156828009.stgit@devbox> References: <154708884117.6325.4454464467156828009.stgit@devbox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prohibit probing on IRQ handlers in irqentry_text because if it interrupts user mode, at that point we haven't changed to kernel space yet and which eventually leads a double fault. E.g. # echo p apic_timer_interrupt > kprobe_events # echo 1 > events/kprobes/enable PANIC: double fault, error_code: 0x0 CPU: 1 PID: 814 Comm: less Not tainted 4.20.0-rc3+ #30 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:error_entry+0x12/0xf0 [snip] Call Trace: ? native_iret+0x7/0x7 ? async_page_fault+0x8/0x30 ? trace_hardirqs_on_thunk+0x1c/0x1c ? error_entry+0x7c/0xf0 ? async_page_fault+0x8/0x30 ? native_iret+0x7/0x7 ? int3+0xa/0x20 ? trace_hardirqs_on_thunk+0x1c/0x1c ? error_entry+0x7c/0xf0 ? int3+0xa/0x20 ? apic_timer_interrupt+0x1/0x20 Kernel panic - not syncing: Machine halted. Kernel Offset: disabled ---[ end Kernel panic - not syncing: Machine halted. ]--- Signed-off-by: Masami Hiramatsu --- arch/x86/kernel/kprobes/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index f4b954ff5b89..fed46ddb1eef 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -1072,6 +1072,13 @@ NOKPROBE_SYMBOL(kprobe_fault_handler); int __init arch_populate_kprobe_blacklist(void) { + int ret; + + ret = kprobe_add_area_blacklist((unsigned long)__irqentry_text_start, + (unsigned long)__irqentry_text_end); + if (ret) + return ret; + return kprobe_add_area_blacklist((unsigned long)__entry_text_start, (unsigned long)__entry_text_end); }