cve-2021-47439
Vulnerability from cvelistv5
Published
2024-05-22 06:19
Modified
2024-12-19 07:42
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
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/383239a33cf29ebee9ce0d4e0e5c900b77a16148
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ef1100ef20f29aec4e62abeccdb5bdbebba1e378
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f2e1de075018cf71bcd7d628e9f759cb8540b0c3
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/383239a33cf29ebee9ce0d4e0e5c900b77a16148
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/ef1100ef20f29aec4e62abeccdb5bdbebba1e378
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/f2e1de075018cf71bcd7d628e9f759cb8540b0c3
Impacted products
Vendor Product Version
Linux Linux Version: 5.7
Show details on NVD website

To clipboard 

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