CVE-2021-47416

Summary

In the Linux kernel, the following vulnerability has been resolved:

phy: mdio: fix memory leak

Syzbot reported memory leak in MDIO bus interface, the problem was in wrong state logic.

MDIOBUS_ALLOCATED indicates 2 states: 1. Bus is only allocated 2. Bus allocated and __mdiobus_register() fails, but device_register() was called

In case of device_register() has been called we should call put_device() to correctly free the memory allocated for this device, but mdiobus_free() calls just kfree(dev) in case of MDIOBUS_ALLOCATED state

To avoid this behaviour we need to set bus->state to MDIOBUS_UNREGISTERED before calling device_register(), because put_device() should be called even in case of device_register() failure.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < 25e9f88c7e3cc35f5e3d3db199660d28a15df639affected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < 2250392d930bd0d989f24d355d6355b0150256e7affected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < f4f502a04ee1e543825af78f47eb7785015cd9f6affected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < 2397b9e118721292429fea8807a698e71b94795faffected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < 414bb4ead1362ef2c8592db723c017258f213988affected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < 0d2dd40a7be61b89a7c99dae8ee96389d27b413aaffected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < 064c2616234a7394867c924b5c1303974f3a4f4daffected
LinuxLinux46abc02175b3c246dd5141d878f565a8725060c9 < ca6e11c337daf7925ff8a2aac8e84490a8691905affected
LinuxLinux2.6.28affected
LinuxLinux0 < 2.6.28unaffected
LinuxLinux4.4.289 <= 4.4.*unaffected
LinuxLinux4.9.287 <= 4.9.*unaffected
LinuxLinux4.14.251 <= 4.14.*unaffected
LinuxLinux4.19.211 <= 4.19.*unaffected
LinuxLinux5.4.153 <= 5.4.*unaffected
LinuxLinux5.10.73 <= 5.10.*unaffected
LinuxLinux5.14.12 <= 5.14.*unaffected
LinuxLinux5.15 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References