Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754474AbaAaWaJ (ORCPT ); Fri, 31 Jan 2014 17:30:09 -0500 Received: from mail.ispras.ru ([83.149.199.45]:59813 "EHLO mail.ispras.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754120AbaAaWaH (ORCPT ); Fri, 31 Jan 2014 17:30:07 -0500 From: Alexey Khoroshilov To: Andrew Morton Cc: Alexey Khoroshilov , linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org Subject: [PATCH] messages: i2o: fix deadlock in compat_ioctl(I2OGETIOPS) Date: Sat, 1 Feb 2014 02:29:48 +0400 Message-Id: <1391207388-7691-1-git-send-email-khoroshilov@ispras.ru> X-Mailer: git-send-email 1.8.3.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org i2o_cfg_compat_ioctl(I2OGETIOPS) locks i2o_cfg_mutex and then calls i2o_cfg_ioctl(I2OGETIOPS) that locks i2o_cfg_mutex as well. A deadlock is guaranteed. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov --- drivers/message/i2o/i2o_config.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/message/i2o/i2o_config.c b/drivers/message/i2o/i2o_config.c index a60c188c2bd9..04bd3b6de401 100644 --- a/drivers/message/i2o/i2o_config.c +++ b/drivers/message/i2o/i2o_config.c @@ -754,19 +754,19 @@ static long i2o_cfg_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg) { int ret; - mutex_lock(&i2o_cfg_mutex); switch (cmd) { case I2OGETIOPS: ret = i2o_cfg_ioctl(file, cmd, arg); break; case I2OPASSTHRU32: + mutex_lock(&i2o_cfg_mutex); ret = i2o_cfg_passthru32(file, cmd, arg); + mutex_unlock(&i2o_cfg_mutex); break; default: ret = -ENOIOCTLCMD; break; } - mutex_unlock(&i2o_cfg_mutex); return ret; } -- 1.8.3.2 -- 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/