Affected: Linux

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

net: marvell: prestera: fix handling IPv4 routes with nhid

Fix handling IPv4 routes referencing a nexthop via its id by replacing calls to fib_info_nh() with fib_info_nhc().

Trying to add an IPv4 route referencing a nextop via nhid:

$ ip link set up swp5 $ ip a a 10.0.0.1/24 dev swp5 $ ip nexthop add dev swp5 id 20 via 10.0.0.2 $ ip route add 10.0.1.0/24 nhid 20

triggers warnings when trying to handle the route:

[ 528.805763] ------------[ cut here ]------------ [ 528.810437] WARNING: CPU: 3 PID: 53 at include/net/nexthop.h:468 __prestera_fi_is_direct+0x2c/0x68 [prestera] [ 528.820434] Modules linked in: prestera_pci act_gact act_police sch_ingress cls_u32 cls_flower prestera arm64_delta_tn48m_dn_led(O) arm64_delta_tn48m_dn_cpld(O) [last unloaded: prestera_pci] [ 528.837485] CPU: 3 PID: 53 Comm: kworker/u8:3 Tainted: G O 6.4.5 #1 [ 528.845178] Hardware name: delta,tn48m-dn (DT) [ 528.849641] Workqueue: prestera_ordered __prestera_router_fib_event_work [prestera] [ 528.857352] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 528.864347] pc : __prestera_fi_is_direct+0x2c/0x68 [prestera] [ 528.870135] lr : prestera_k_arb_fib_evt+0xb20/0xd50 [prestera] [ 528.876007] sp : ffff80000b20bc90 [ 528.879336] x29: ffff80000b20bc90 x28: 0000000000000000 x27: ffff0001374d3a48 [ 528.886510] x26: ffff000105604000 x25: ffff000134af8a28 x24: ffff0001374d3800 […