CVE-2021-47439

net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work

Description

In the Linux kernel, the following vulnerability has been resolved: net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work When the ksz module is installed and removed using rmmod, kernel crashes with null pointer dereferrence error. During rmmod, ksz_switch_remove function tries to cancel the mib_read_workqueue using cancel_delayed_work_sync routine and unregister switch from dsa. During dsa_unregister_switch it calls ksz_mac_link_down, which in turn reschedules the workqueue since mib_interval is non-zero. Due to which queue executed after mib_interval and it tries to access dp->slave. But the slave is unregistered in the ksz_switch_remove function. Hence kernel crashes. To avoid this crash, before canceling the workqueue, resetted the mib_interval to 0. v1 -> v2: -Removed the if condition in ksz_mib_read_work

Category

5.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.03%
Affected: Linux Linux
Affected: Linux Linux
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-47439?
CVE-2021-47439 has been scored as a medium severity vulnerability.
How to fix CVE-2021-47439?
To fix CVE-2021-47439, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-47439 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-47439 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-47439?
CVE-2021-47439 affects Linux Linux, Linux Linux.
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