diff options
| author | Jason Gunthorpe <jgg@nvidia.com> | 2021-04-06 16:40:25 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-05-14 09:50:26 +0200 |
| commit | b29d6a435e0f9a8a65dc9b435572a21a79914d91 (patch) | |
| tree | 5c2aa71abbee3bc6f3175689e628df9737c0cccb /drivers/vfio/mdev | |
| parent | 87856f9af04eaacf9848710625a4ffee1d020fa9 (diff) | |
vfio/mdev: Do not allow a mdev_type to have a NULL parent pointer
[ Upstream commit b5a1f8921d5040bb788492bf33a66758021e4be5 ]
There is a small race where the parent is NULL even though the kobj has
already been made visible in sysfs.
For instance the attribute_group is made visible in sysfs_create_files()
and the mdev_type_attr_show() does:
ret = attr->show(kobj, type->parent->dev, buf);
Which will crash on NULL parent. Move the parent setup to before the type
pointer leaves the stack frame.
Fixes: 7b96953bc640 ("vfio: Mediated device Core driver")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <2-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/vfio/mdev')
| -rw-r--r-- | drivers/vfio/mdev/mdev_sysfs.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c index 917fd84c1c6f..367ff5412a38 100644 --- a/drivers/vfio/mdev/mdev_sysfs.c +++ b/drivers/vfio/mdev/mdev_sysfs.c @@ -105,6 +105,7 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent, return ERR_PTR(-ENOMEM); type->kobj.kset = parent->mdev_types_kset; + type->parent = parent; ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL, "%s-%s", dev_driver_string(parent->dev), @@ -132,7 +133,6 @@ static struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent, } type->group = group; - type->parent = parent; return type; attrs_failed: |