NetSight
medium5.5

CVE-2022-49339

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: unexport __init-annotated seg6_hmac_init() EXPORT_SYMBOL and __init is a bad com…

Impact

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: unexport __init-annotated seg6_hmac_init() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the caller (net/ipv6/seg6.c) and the callee (net/ipv6/seg6_hmac.c) belong to the same module. It seems an internal function call in ipv6.ko.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 4.10 before 4.14.283
from 4.15 before 4.19.247
from 4.20 before 5.4.198
from 5.5 before 5.10.122
from 5.11 before 5.15.47
from 5.16 before 5.17.15

References