From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753314AbcAIDv3 (ORCPT ); Fri, 8 Jan 2016 22:51:29 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:46978 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751284AbcAIDv2 (ORCPT ); Fri, 8 Jan 2016 22:51:28 -0500 Date: Sat, 9 Jan 2016 03:51:25 +0000 From: Al Viro To: Richard Weinberger Cc: user-mode-linux-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] um: Fix get_signal() usage Message-ID: <20160109035125.GA365@ZenIV.linux.org.uk> References: <1447836703-32594-1-git-send-email-richard@nod.at> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1447836703-32594-1-git-send-email-richard@nod.at> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 18, 2015 at 09:51:43AM +0100, Richard Weinberger wrote: > If get_signal() returns us a signal to post > we must not call it again, otherwise the already > posted signal will be overridden. > Before commit a610d6e672d this was the case as we stopped > the while after a successful handle_signal(). Old behaviour had been wrong. If you have several pending signals, more than one sigframe should be built, as if the second, etc. had been delivered right on the entry into the handler. Stopping after the first one is obviously wrong - consider the case when attempt to deliver it has raised SIGSEGV.