CVE-2023-52439: uio: Fix use-after-free in uio_open
In the Linux kernel, the following vulnerability has been resolved:
uio: Fix use-after-free in uioopen
core-1 core-2 ------------------------------------------------------- uiounregisterdevice uioopen idev = idrfind() deviceunregister(&idev->dev) putdevice(&idev->dev) uiodevicerelease getdevice(&idev->dev) kfree(idev) uiofreeminor(minor) uiorelease putdevice(&idev->dev) kfree(idev) -------------------------------------------------------
In the core-1 uiounregisterdevice(), the deviceunregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 deviceunregister, putdevice and before doing kfree, the core-2 may getdevice. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uiorelease and putdevice, the idev will be double freed.
To address this issue, we can get idev atomic & inc idev reference with minorlock.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.223-1Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/0c9ae0b8605078eafc3bea053cc78791e97ba2e2 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/17a8519cb359c3b483fb5c7367efa9a8a508bdea - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/3174e0f7de1ba392dc191625da83df02d695b60c - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/35f102607054faafe78d2a6994b18d5d9d6e92ad - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/5cf604ee538ed0c467abe3b4cda5308a6398f0f7 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/5e0be1229ae199ebb90b33102f74a0f22d152570 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/913205930da6213305616ac539447702eaa85e41 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch git.kernel.org/stable/c/e93da893d52d82d57fc0db2ca566024e0f26ff50
Event History
Frequently Asked Questions
What is the severity of CVE-2023-52439?
CVE-2023-52439 has a moderate severity level due to its potential for a use-after-free vulnerability in the Linux kernel.
How do I fix CVE-2023-52439?
To fix CVE-2023-52439, upgrade to a patched version of the Linux kernel such as 5.10.223-1 or higher.
Which versions of the Linux kernel are affected by CVE-2023-52439?
CVE-2023-52439 affects Linux kernel versions from 4.18.0 to 6.6.13, excluding version 5.10.223 and higher.
Can CVE-2023-52439 be exploited remotely?
CVE-2023-52439 may allow local users to gain elevated privileges, but it does not appear to be exploitable remotely.
What components of the Linux kernel are impacted by CVE-2023-52439?
CVE-2023-52439 impacts the User Input/Output (uio) subsystem within the Linux kernel.