From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:33628 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932790AbeGAQZJ (ORCPT ); Sun, 1 Jul 2018 12:25:09 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Neuling , Michael Ellerman Subject: [PATCH 4.9 025/101] powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG Date: Sun, 1 Jul 2018 18:21:11 +0200 Message-Id: <20180701160758.152657125@linuxfoundation.org> In-Reply-To: <20180701160757.138608453@linuxfoundation.org> References: <20180701160757.138608453@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Neuling commit 4f7c06e26ec9cf7fe9f0c54dc90079b6a4f4b2c3 upstream. In commit e2a800beaca1 ("powerpc/hw_brk: Fix off by one error when validating DAWR region end") we fixed setting the DAWR end point to its max value via PPC_PTRACE_SETHWDEBUG. Unfortunately we broke PTRACE_SET_DEBUGREG when setting a 512 byte aligned breakpoint. PTRACE_SET_DEBUGREG currently sets the length of the breakpoint to zero (memset() in hw_breakpoint_init()). This worked with arch_validate_hwbkpt_settings() before the above patch was applied but is now broken if the breakpoint is 512byte aligned. This sets the length of the breakpoint to 8 bytes when using PTRACE_SET_DEBUGREG. Fixes: e2a800beaca1 ("powerpc/hw_brk: Fix off by one error when validating DAWR region end") Cc: stable@vger.kernel.org # v3.11+ Signed-off-by: Michael Neuling Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/ptrace.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -2380,6 +2380,7 @@ static int ptrace_set_debugreg(struct ta /* Create a new breakpoint request if one doesn't exist already */ hw_breakpoint_init(&attr); attr.bp_addr = hw_brk.address; + attr.bp_len = 8; arch_bp_generic_fields(hw_brk.type, &attr.bp_type);