DocumentationOverview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
net: phy: sfp: free mii_bus in sfp_i2c_mdiobus_destroy
sfp_i2c_mdiobus_create() allocates the I2C MDIO bus with mdio_i2c_alloc(), a plain (non-devm) allocation, and registers it. sfp_i2c_mdiobus_destroy() only unregisters the bus and clears sfp->i2c_mii without calling mdiobus_free(). As the only reference to the bus is then cleared, the struct mii_bus is leaked.
This is hit whenever a copper/RollBall SFP module that instantiated an MDIO bus is removed: sfp_sm_main() takes the global teardown path and calls sfp_i2c_mdiobus_destroy(). sfp_cleanup(), on driver unbind, frees sfp->i2c_mii directly, which is why the leak only triggered on module hot-removal and not on unbind.
Free the bus in sfp_i2c_mdiobus_destroy() to match the allocation done in sfp_i2c_mdiobus_create().
Details
- Affected product:
- Debian 10 ELS
- Affected packages:
- linux @ 4.19.0
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 13 | Released |
13 kernels
|
| Ubuntu 24.04 | Planned | — |
| Ubuntu 24.04 AWS | Planned | — |
| Ubuntu 26.04 | Will Not Fix | — |