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,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 94001C433DF for ; Tue, 23 Jun 2020 17:39:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 645B32078A for ; Tue, 23 Jun 2020 17:39:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592933999; bh=yjNpRv8q3GfXREcKPByLoH2E7axhZx/JhrTgyTbmn9k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kUAlAidjkff+hiagDmUuwZHgdz0k/uVmlAa64ybeveUhQWIe+ZwJ8J3vF8/gEDNrq 4nbYadRcq2KCl/WVQqHFKy/K6XLjNTbBUxm4TQRBjLA/V7CQPk7fuaLgXJP5ZF52gw PV0m9gF1FrfKYjyYTJA5PkSOV0/Gfga9BUS9kH6o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387691AbgFWRj6 (ORCPT ); Tue, 23 Jun 2020 13:39:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:33350 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387532AbgFWRgR (ORCPT ); Tue, 23 Jun 2020 13:36:17 -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 112B220774; Tue, 23 Jun 2020 17:36:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592933776; bh=yjNpRv8q3GfXREcKPByLoH2E7axhZx/JhrTgyTbmn9k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QWFA8Hqp+0FLPhAG1DBELN+UW2kZcs1FbVJr5OcrQy/g4CRZCQKmQdPGSLVUVytIE 6pfeUT9oyC1Eny2dhei9JjtXZwvgo7249FPXjsG0/5+j5G7MTKtDcRtu614s6PlxJH JfOBjTLrL43nHx+pyzjzSt6ytCUW55G/DO8+dK1c= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sven Schnelle , Vasily Gorbik , Sasha Levin , linux-s390@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 14/24] s390/ptrace: pass invalid syscall numbers to tracing Date: Tue, 23 Jun 2020 13:35:49 -0400 Message-Id: <20200623173559.1355728-14-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200623173559.1355728-1-sashal@kernel.org> References: <20200623173559.1355728-1-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: Sven Schnelle [ Upstream commit 00332c16b1604242a56289ff2b26e283dbad0812 ] tracing expects to see invalid syscalls, so pass it through. The syscall path in entry.S checks the syscall number before looking up the handler, so it is still safe. Signed-off-by: Sven Schnelle Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin --- arch/s390/kernel/entry.S | 2 +- arch/s390/kernel/ptrace.c | 6 ++---- 2 files changed, 3 insertions(+), 5 deletions(-) diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index bc85987727f09..c544b7a11ebb3 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -368,9 +368,9 @@ ENTRY(system_call) jnz .Lsysc_nr_ok # svc 0: system call number in %r1 llgfr %r1,%r1 # clear high word in r1 + sth %r1,__PT_INT_CODE+2(%r11) cghi %r1,NR_syscalls jnl .Lsysc_nr_ok - sth %r1,__PT_INT_CODE+2(%r11) slag %r8,%r1,3 .Lsysc_nr_ok: xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c index ad71132374f0c..5a2b1501d9983 100644 --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -844,11 +844,9 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) * call number to gprs[2]. */ if (test_thread_flag(TIF_SYSCALL_TRACE) && - (tracehook_report_syscall_entry(regs) || - regs->gprs[2] >= NR_syscalls)) { + tracehook_report_syscall_entry(regs)) { /* - * Tracing decided this syscall should not happen or the - * debugger stored an invalid system call number. Skip + * Tracing decided this syscall should not happen. Skip * the system call and the system call restart handling. */ clear_pt_regs_flag(regs, PIF_SYSCALL); -- 2.25.1