Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756434Ab1DRSy3 (ORCPT ); Mon, 18 Apr 2011 14:54:29 -0400 Received: from smtp.ispras.ru ([83.149.198.202]:44275 "EHLO smtp.ispras.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756354Ab1DRSy1 (ORCPT ); Mon, 18 Apr 2011 14:54:27 -0400 From: Alexey Khoroshilov To: Eric Moore , Kashyap Desai Cc: "James E.J. Bottomley" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Alexey Khoroshilov Subject: [PATCH] [SCSI] mpt2sas: fix double mutex lock in NON_BLOCKING state Date: Mon, 18 Apr 2011 22:53:38 +0400 Message-Id: <1303152818-9856-1-git-send-email-khoroshilov@ispras.ru> X-Mailer: git-send-email 1.7.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2459 Lines: 74 If mutex_trylock succeed, the control flow goes to mutex_lock_interruptible() that is not a good thing. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov --- drivers/scsi/mpt2sas/mpt2sas_ctl.c | 24 ++++++++++++++++-------- 1 files changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c b/drivers/scsi/mpt2sas/mpt2sas_ctl.c index 1c6d2b4..9bd7ffc 100644 --- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c +++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c @@ -648,8 +648,10 @@ _ctl_do_mpt_command(struct MPT2SAS_ADAPTER *ioc, issue_reset = 0; - if (state == NON_BLOCKING && !mutex_trylock(&ioc->ctl_cmds.mutex)) - return -EAGAIN; + if (state == NON_BLOCKING) { + if (!mutex_trylock(&ioc->ctl_cmds.mutex)) + return -EAGAIN; + } else if (mutex_lock_interruptible(&ioc->ctl_cmds.mutex)) return -ERESTARTSYS; @@ -1587,8 +1589,10 @@ _ctl_diag_register(void __user *arg, enum block_state state) if (_ctl_verify_adapter(karg.hdr.ioc_number, &ioc) == -1 || !ioc) return -ENODEV; - if (state == NON_BLOCKING && !mutex_trylock(&ioc->ctl_cmds.mutex)) - return -EAGAIN; + if (state == NON_BLOCKING) { + if (!mutex_trylock(&ioc->ctl_cmds.mutex)) + return -EAGAIN; + } else if (mutex_lock_interruptible(&ioc->ctl_cmds.mutex)) return -ERESTARTSYS; rc = _ctl_diag_register_2(ioc, &karg); @@ -1932,8 +1936,10 @@ _ctl_diag_release(void __user *arg, enum block_state state) return 0; } - if (state == NON_BLOCKING && !mutex_trylock(&ioc->ctl_cmds.mutex)) - return -EAGAIN; + if (state == NON_BLOCKING) { + if (!mutex_trylock(&ioc->ctl_cmds.mutex)) + return -EAGAIN; + } else if (mutex_lock_interruptible(&ioc->ctl_cmds.mutex)) return -ERESTARTSYS; @@ -2033,8 +2039,10 @@ _ctl_diag_read_buffer(void __user *arg, enum block_state state) } /* Get a free request frame and save the message context. */ - if (state == NON_BLOCKING && !mutex_trylock(&ioc->ctl_cmds.mutex)) - return -EAGAIN; + if (state == NON_BLOCKING) { + if (!mutex_trylock(&ioc->ctl_cmds.mutex)) + return -EAGAIN; + } else if (mutex_lock_interruptible(&ioc->ctl_cmds.mutex)) return -ERESTARTSYS; -- 1.7.1 -- 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/