diff options
| author | Guanghui Feng <guanghuifeng@linux.alibaba.com> | 2023-12-21 12:57:43 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-01-04 19:03:47 +0300 |
| commit | 0c9ae0b8605078eafc3bea053cc78791e97ba2e2 (patch) | |
| tree | c9b91096cecdf801ae8b8b0cd4bdcaf18023b299 /drivers/iio/adc/spear_adc.c | |
| parent | 97d62760e441af9ed393e127a46172f9534b5808 (diff) | |
| download | linux-0c9ae0b8605078eafc3bea053cc78791e97ba2e2.tar.xz | |
uio: Fix use-after-free in uio_open
core-1 core-2
-------------------------------------------------------
uio_unregister_device uio_open
idev = idr_find()
device_unregister(&idev->dev)
put_device(&idev->dev)
uio_device_release
get_device(&idev->dev)
kfree(idev)
uio_free_minor(minor)
uio_release
put_device(&idev->dev)
kfree(idev)
-------------------------------------------------------
In the core-1 uio_unregister_device(), the device_unregister will kfree
idev when the idev->dev kobject ref is 1. But after core-1
device_unregister, put_device and before doing kfree, the core-2 may
get_device. Then:
1. After core-1 kfree idev, the core-2 will do use-after-free for idev.
2. When core-2 do uio_release and put_device, the idev will be double
freed.
To address this issue, we can get idev atomic & inc idev reference with
minor_lock.
Fixes: 57c5f4df0a5a ("uio: fix crash after the device is unregistered")
Cc: stable <stable@kernel.org>
Signed-off-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Link: https://lore.kernel.org/r/1703152663-59949-1-git-send-email-guanghuifeng@linux.alibaba.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio/adc/spear_adc.c')
0 files changed, 0 insertions, 0 deletions