CVE-2021-47439 (GCVE-0-2021-47439)
Vulnerability from cvelistv5
Published
2024-05-22 06:19
Modified
2026-05-11 13:54
Severity ?
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
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
References
Impacted products
Vendor Product Version
Linux Linux Version: 469b390e1ba330e888175e55d78573db2e9a8cb4
Version: 469b390e1ba330e888175e55d78573db2e9a8cb4
Version: 469b390e1ba330e888175e55d78573db2e9a8cb4
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