CVE intelligence and bounded remediation

CVE-2022-49092 — Linux Linux Kernel security vulnerability

In the Linux kernel, the following vulnerability has been resolved: net: ipv4: fix route with nexthop object delete warning FRR folks have hit a kernel warning[1] while deleting routes[2] which is caused by trying to delete a route pointing to a nexthop id without specifying nhid but matching on an interface. That is, a route is found but we hit a warning while matching it. The warning is from fib_info_nh() in include/net/nexthop.h because we run it on a fib_info with nexthop object. The call chain is: inet_rtm_delroute -> fib_table_delete -> fib_nh_match (called with a nexthop fib_info and also with fc_oif set thus calling fib_info_nh on the fib_info and triggering the warning). The fix is to not do any matching in that branch if the fi has a nexthop object because those are managed separately. I.e. we should match when deleting without nh spec and should fail when deleting a nexthop route with old-style nh spec because nexthop objects are managed separately, e.g.: $ ip r show 1.2.3.4/32 1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0 $ ip r del 1.2.3.4/32 $ ip r del 1.2.3.4/32 nhid 12 <both should work> $ ip r del 1.2.3.4/32 dev dummy0 <should fail with ESRCH> [1] [ 523.462226]…

Severity

Medium

CVSS

5.5 (3.1)

Published

2025-02-26

CISA KEV

Not currently listed

Ecosystem

linux/kernel