linux-kernel - [PATCH] vfio: fix crash on rmmod

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 for Android: free password hash cracker in your pocket

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

Message-Id: <1370412194-32211-1-git-send-email-aik@ozlabs.ru>
Date:	Wed,  5 Jun 2013 16:03:14 +1000
From:	Alexey Kardashevskiy <aik@...abs.ru>
To:	Alex Williamson <alex.williamson@...hat.com>
Cc:	Alexey Kardashevskiy <aik@...abs.ru>, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] vfio: fix crash on rmmod

devtmpfs_delete_node() calls devnode() callback with mode==NULL but
vfio still tries to write there.

The patch fixes this.

Signed-off-by: Alexey Kardashevskiy <aik@...abs.ru>

---

Steps to reproduce on freshly booted system with no devices given to VFIO:
modprobe vfio
rmmod vfio_iommu_spapr_tce
rmmod vfio
---
 drivers/vfio/vfio.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 523c121..259ad28 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1360,7 +1360,7 @@ static const struct file_operations vfio_device_fops = {
  */
 static char *vfio_devnode(struct device *dev, umode_t *mode)
 {
-	if (MINOR(dev->devt) == 0)
+	if (mode && (MINOR(dev->devt) == 0))
 		*mode = S_IRUGO | S_IWUGO;
 
 	return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/