cvedb.io
CVE-2021-47555
HIGH · CVSS 7.8
EPSS exploitation probability: 0%
Published 2024-05-24T15:15:20.237 · Last modified 2026-08-04T10:17:08.653

Summary

In the Linux kernel, the following vulnerability has been resolved: net: vlan: fix underflow for the real_dev refcnt Inject error before dev_hold(real_dev) in register_vlan_dev(), and execute the following testcase: ip link add dev dummy1 type dummy ip link add name dummy1.100 link dummy1 type vlan id 100 ip link del dev dummy1 When the dummy netdevice is removed, we will get a WARNING as following: ======================================================================= refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 2 PID: 0 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 and an endless loop of: ======================================================================= unregister_netdevice: waiting for dummy1 to become free. Usage count = -1073741824 That is because

Affected products

linux — linux_kernel

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.