CVE-2022-50043

Summary

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

net: fix potential refcount leak in ndisc_router_discovery()

The issue happens on specific paths in the function. After both the object rt and neigh are grabbed successfully, when lifetime is nonzero but the metric needs change, the function just deletes the route and set rt to NULL. Then, it may try grabbing rt and neigh again if above conditions hold. The function simply overwrite neigh if succeeds or returns if fails, without decreasing the reference count of previous neigh. This may result in memory leaks.

Fix it by decrementing the reference count of neigh in place.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux6b2e04bc240fe9be9e690059f710e9f95346d34d < ffb15594433391fd7885eb88ce5a7f7bdeefbb15affected
LinuxLinux6b2e04bc240fe9be9e690059f710e9f95346d34d < 7998043d31d000c3a93f46182e6569dd0eecda34affected
LinuxLinux6b2e04bc240fe9be9e690059f710e9f95346d34d < 7396ba87f1edf549284869451665c7c4e74ecd4faffected
LinuxLinux5.12affected
LinuxLinux0 < 5.12unaffected
LinuxLinux5.15.63 <= 5.15.*unaffected
LinuxLinux5.19.4 <= 5.19.*unaffected
LinuxLinux6.0 <= *unaffected

Weaknesses

References