linux-kernel - [PATCH 4.9 166/177] vt6655: Fix a possible sleep-in-atomic bug in vt6655

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20171218152918.635996419@linuxfoundation.org>
Date:   Mon, 18 Dec 2017 16:49:49 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Jia-Ju Bai <baijiaju1990@....com>,
        Sasha Levin <alexander.levin@...izon.com>
Subject: [PATCH 4.9 166/177] vt6655: Fix a possible sleep-in-atomic bug in vt6655_suspend

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jia-Ju Bai <baijiaju1990@....com>


[ Upstream commit 42c8eb3f6e15367981b274cb79ee4657e2c6949d ]

The driver may sleep under a spinlock, and the function call path is:
vt6655_suspend (acquire the spinlock)
  pci_set_power_state
    __pci_start_power_transition (drivers/pci/pci.c)
      msleep --> may sleep

To fix it, pci_set_power_state is called without having a spinlock.

This bug is found by my static analysis tool and my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@....com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@...izon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/staging/vt6655/device_main.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/staging/vt6655/device_main.c
+++ b/drivers/staging/vt6655/device_main.c
@@ -1698,10 +1698,11 @@ static int vt6655_suspend(struct pci_dev
 	MACbShutdown(priv);
 
 	pci_disable_device(pcid);
-	pci_set_power_state(pcid, pci_choose_state(pcid, state));
 
 	spin_unlock_irqrestore(&priv->lock, flags);
 
+	pci_set_power_state(pcid, pci_choose_state(pcid, state));
+
 	return 0;
 }