Executive brief
A vulnerability in the Linux kernel's networking component could lead to system instability or crashes. When certain network hardware (SFP modules) fails to initialize properly, the system fails to clean up internal references, leading to a 'dangling pointer.' This could cause the system to malfunction or crash during subsequent hardware events.
Technical details
A resource management vulnerability exists in the Linux kernel's PHY library (drivers/net/phy/phy_device.c). When the `phy_probe` or `phy_sfp_probe` functions fail, the kernel does not call `sfp_bus_del_upstream()`, leaving a dangling 'upstream' field in the SFP bus structure. This pointer may be dereferenced during later SFP events, potentially leading to a kernel oops or unpredictable behavior. The issue affects versions from 5.5 up to the fix in 7.1 and has been resolved by ensuring proper cleanup in the error paths.
Affected products
- Linux Linux Kernel 5.5 to 7.1
Timeline
- 2026-06-25: disclosed
- 2026-06-25: advisory