Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755411AbaLEXx5 (ORCPT ); Fri, 5 Dec 2014 18:53:57 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:53755 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751852AbaLEWpv (ORCPT ); Fri, 5 Dec 2014 17:45:51 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oleg Nesterov , Srikar Dronamraju , Borislav Petkov , Andy Lutomirski , Linus Torvalds Subject: [PATCH 3.17 018/122] uprobes, x86: Fix _TIF_UPROBE vs _TIF_NOTIFY_RESUME Date: Fri, 5 Dec 2014 14:43:12 -0800 Message-Id: <20141205223308.281461978@linuxfoundation.org> X-Mailer: git-send-email 2.1.3 In-Reply-To: <20141205223305.514276242@linuxfoundation.org> References: <20141205223305.514276242@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Lutomirski commit 82975bc6a6df743b9a01810fb32cb65d0ec5d60b upstream. x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but not on non-paranoid returns. I suspect that this is a mistake and that the code only works because int3 is paranoid. Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround for the x86 bug. With that bug fixed, we can remove _TIF_NOTIFY_RESUME from the uprobes code. Reported-by: Oleg Nesterov Acked-by: Srikar Dronamraju Acked-by: Borislav Petkov Signed-off-by: Andy Lutomirski Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/thread_info.h | 2 +- kernel/events/uprobes.c | 1 - 2 files changed, 1 insertion(+), 2 deletions(-) --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -141,7 +141,7 @@ struct thread_info { /* Only used for 64 bit */ #define _TIF_DO_NOTIFY_MASK \ (_TIF_SIGPENDING | _TIF_MCE_NOTIFY | _TIF_NOTIFY_RESUME | \ - _TIF_USER_RETURN_NOTIFY) + _TIF_USER_RETURN_NOTIFY | _TIF_UPROBE) /* flags to check in __switch_to() */ #define _TIF_WORK_CTXSW \ --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1640,7 +1640,6 @@ bool uprobe_deny_signal(void) if (__fatal_signal_pending(t) || arch_uprobe_xol_was_trapped(t)) { utask->state = UTASK_SSTEP_TRAPPED; set_tsk_thread_flag(t, TIF_UPROBE); - set_tsk_thread_flag(t, TIF_NOTIFY_RESUME); } } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/