Description: ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
References:
Notes:
 carnil> Introduced in f88d8ea67fbdb ("ipv6: Plumb support for nexthop object in a
 carnil> fib6_info")
 carnil> 706ec91916462 ("ipv6: Fix nexthop refcnt leak when creating ipv6 route info").
 carnil> Vulnerable versions: 5.3-rc1 5.4.58 5.7.15 5.8.
Bugs:
upstream: released (5.13-rc5) [821bbf79fe46a8b1d18aa456e8ed0a3c208c3754]
6.7-upstream-stable: N/A "Fixed before branching point"
6.6-upstream-stable: N/A "Fixed before branching point"
6.1-upstream-stable: N/A "Fixed before branching point"
5.10-upstream-stable: released (5.10.43) [09870235827451409ff546b073d754a19fd17e2e]
4.19-upstream-stable: N/A "Vulnerable code not present"
sid: released (5.10.46-1)
6.1-bookworm-security: N/A "Fixed before branching point"
5.10-bullseye-security: N/A "Fixed before branching point"
4.19-buster-security: N/A "Vulnerable code not present"