CVE-2023-52449: mtd: Fix gluebi NULL pointer dereference caused by ftl notifier
In the Linux kernel, the following vulnerability has been resolved:
mtd: Fix gluebi NULL pointer dereference caused by ftl notifier
If both ftl.ko and gluebi.ko are loaded, the notifier of ftl triggers NULL pointer dereference when trying to access ‘gluebi->desc’ in gluebiread().
ubigluebiinit ubiregistervolumenotifier ubienumeratevolumes ubinotifyall gluebinotify nb->notifiercall() gluebicreate mtddeviceregister mtddeviceparseregister addmtddevice blktransnotifyadd not->add() ftladdmtd tr->addmtd() scanheader mtdread mtdreadoob mtdreadoobstd gluebiread mtd->read() gluebi->desc - NULL
Detailed reproduction information available at the Link [1],
In the normal case, obtain gluebi->desc in the gluebigetdevice(), and access gluebi->desc in the gluebiread(). However, gluebigetdevice() is not executed in advance in the ftladdmtd() process, which leads to NULL pointer dereference.
The solution for the gluebi module is to run jffs2 on the UBI volume without considering working with ftl or mtdblock [2]. Therefore, this problem can be avoided by preventing gluebi from creating the mtdblock device after creating mtd partition of the type MTDUBIVOLUME.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2023-52449?
CVE-2023-52449 is classified as a potential high-severity vulnerability due to the risk of a NULL pointer dereference in the Linux kernel.
How do I fix CVE-2023-52449?
To mitigate CVE-2023-52449, update the Linux kernel to one of the patched versions listed in the vulnerability report.
What impact does CVE-2023-52449 have on my system?
CVE-2023-52449 may lead to a crash or denial of service on systems where both ftl.ko and gluebi.ko modules are loaded.
Which Linux kernel versions are affected by CVE-2023-52449?
CVE-2023-52449 affects specific Linux kernel versions between 2.6.31 to 6.12.10.
Is my system safe from CVE-2023-52449 if I am not using ftl.ko and gluebi.ko?
If ftl.ko and gluebi.ko are not loaded, your system may be less exposed, but it is advisable to apply security updates regardless.