From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933148Ab3BYWbs (ORCPT ); Mon, 25 Feb 2013 17:31:48 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55165 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759930Ab3BYWUI (ORCPT ); Mon, 25 Feb 2013 17:20:08 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Roman Rakus , Lingzhu Xiang , Oleg Nesterov , Jiri Slaby Subject: [ 17/58] tty: set_termios/set_termiox should not return -EINTR Date: Mon, 25 Feb 2013 14:19:13 -0800 Message-Id: <20130225221639.701366903@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130225221636.018756060@linuxfoundation.org> References: <20130225221636.018756060@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oleg Nesterov commit 183d95cdd834381c594d3aa801c1f9f9c0c54fa9 upstream. See https://bugzilla.redhat.com/show_bug.cgi?id=904907 read command causes bash to abort with double free or corruption (out). A simple test-case from Roman: // Compile the reproducer and send sigchld ti that process. // EINTR occurs even if SA_RESTART flag is set. void handler(int sig) { } main() { struct sigaction act; act.sa_handler = handler; act.sa_flags = SA_RESTART; sigaction (SIGCHLD, &act, 0); struct termio ttp; ioctl(0, TCGETA, &ttp); while(1) { if (ioctl(0, TCSETAW, ttp) < 0) { if (errno == EINTR) { fprintf(stderr, "BUG!"); return(1); } } } } Change set_termios/set_termiox to return -ERESTARTSYS to fix this particular problem. I didn't dare to change other EINTR's in drivers/tty/, but they look equally wrong. Reported-by: Roman Rakus Reported-by: Lingzhu Xiang Signed-off-by: Oleg Nesterov Cc: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ioctl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -617,7 +617,7 @@ static int set_termios(struct tty_struct if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) - return -EINTR; + return -ERESTARTSYS; } tty_set_termios(tty, &tmp_termios); @@ -684,7 +684,7 @@ static int set_termiox(struct tty_struct if (opt & TERMIOS_WAIT) { tty_wait_until_sent(tty, 0); if (signal_pending(current)) - return -EINTR; + return -ERESTARTSYS; } mutex_lock(&tty->termios_mutex);