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Unrated severityNVD Advisory· Published May 22, 2024· Updated May 4, 2025

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

CVE-2021-47439

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

Affected products

100

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

3

News mentions

0

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