In the Linux kernel, the following vulnerability has been resolved:
net, neigh: Do not trigger immediate probes on NUD_FAILED from neigh_managed_work
syzkaller was able to trigger a deadlock for NTF_MANAGED entries [0]:
kworker/0:16/14617 is trying to acquire lock: ffffffff8d4dd370 (&tbl->lock){++-.}-{2:2}, at: ___neigh_create+0x9e1/0x2990 net/core/neighbour.c:652 […] but task is already holding lock: ffffffff8d4dd370 (&tbl->lock){++-.}-{2:2}, at: neigh_managed_work+0x35/0x250 net/core/neighbour.c:1572
The neighbor entry turned to NUD_FAILED state, where __neigh_event_send() triggered an immediate probe as per commit cd28ca0a3dd1 (neigh: reduce arp latency) via neigh_probe() given table lock was held.
One option to fix this situation is to defer the neigh_probe() back to the neigh_timer_handler() similarly as pre cd28ca0a3dd1. For the case of NTF_MANAGED, this deferral is acceptable given this only happens on actual failure state and regular / expected state is NUD_VALID with the entry already present.
The fix adds a parameter to __neigh_event_send() in order to communicate whether immediate probe is allowed or disallowed. Existing call-sites of neigh_event_send() default as-is to immediate probe. However, the neigh_managed_work() disables it via use of neigh_event_send_probe().
[0] __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:334 ___neigh_create+0x9e1/0x2990 net/core/neighbour.c:652 ip6_finish_output2+0x1070/0x14f0 net/ipv6/ip6_output.c:123 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline] __ip6_finish_output+0x61e/0xe90 net/ipv6/ip6_output.c:170 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa99/0x17f0 net/ipv6/ndisc.c:508 ndisc_send_ns+0x3a9/0x840 net/ipv6/ndisc.c:650 ndisc_solicit+0x2cd/0x4f0 net/ipv6/ndisc.c:742 neigh_probe+0xc2/0x110 net/core/neighbour.c:1040 __neigh_event_send+0x37d/0x1570 net/core/neighbour.c:1201 neigh_event_send include/net/neighbour.h:470 [inline] neigh_managed_work+0x162/0x250 net/core/neighbour.c:1574 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Name | Vendor | Start Version | End Version |
---|---|---|---|
Linux | Ubuntu | upstream | * |
Linux-allwinner-5.19 | Ubuntu | jammy | * |
Linux-allwinner-5.19 | Ubuntu | upstream | * |
Linux-aws | Ubuntu | upstream | * |
Linux-aws-5.0 | Ubuntu | esm-infra/bionic | * |
Linux-aws-5.0 | Ubuntu | upstream | * |
Linux-aws-5.11 | Ubuntu | focal | * |
Linux-aws-5.11 | Ubuntu | upstream | * |
Linux-aws-5.13 | Ubuntu | focal | * |
Linux-aws-5.13 | Ubuntu | upstream | * |
Linux-aws-5.15 | Ubuntu | upstream | * |
Linux-aws-5.19 | Ubuntu | jammy | * |
Linux-aws-5.19 | Ubuntu | upstream | * |
Linux-aws-5.3 | Ubuntu | esm-infra/bionic | * |
Linux-aws-5.3 | Ubuntu | upstream | * |
Linux-aws-5.4 | Ubuntu | upstream | * |
Linux-aws-5.8 | Ubuntu | focal | * |
Linux-aws-5.8 | Ubuntu | upstream | * |
Linux-aws-6.2 | Ubuntu | jammy | * |
Linux-aws-6.2 | Ubuntu | upstream | * |
Linux-aws-6.5 | Ubuntu | upstream | * |
Linux-aws-fips | Ubuntu | upstream | * |
Linux-aws-hwe | Ubuntu | upstream | * |
Linux-azure | Ubuntu | esm-infra/bionic | * |
Linux-azure | Ubuntu | upstream | * |
Linux-azure-4.15 | Ubuntu | upstream | * |
Linux-azure-5.11 | Ubuntu | focal | * |
Linux-azure-5.11 | Ubuntu | upstream | * |
Linux-azure-5.13 | Ubuntu | focal | * |
Linux-azure-5.13 | Ubuntu | upstream | * |
Linux-azure-5.15 | Ubuntu | upstream | * |
Linux-azure-5.19 | Ubuntu | jammy | * |
Linux-azure-5.19 | Ubuntu | upstream | * |
Linux-azure-5.3 | Ubuntu | esm-infra/bionic | * |
Linux-azure-5.3 | Ubuntu | upstream | * |
Linux-azure-5.4 | Ubuntu | upstream | * |
Linux-azure-5.8 | Ubuntu | focal | * |
Linux-azure-5.8 | Ubuntu | upstream | * |
Linux-azure-6.2 | Ubuntu | jammy | * |
Linux-azure-6.2 | Ubuntu | upstream | * |
Linux-azure-6.5 | Ubuntu | upstream | * |
Linux-azure-edge | Ubuntu | esm-infra/bionic | * |
Linux-azure-edge | Ubuntu | upstream | * |
Linux-azure-fde | Ubuntu | focal | * |
Linux-azure-fde | Ubuntu | upstream | * |
Linux-azure-fde-5.15 | Ubuntu | upstream | * |
Linux-azure-fde-5.19 | Ubuntu | jammy | * |
Linux-azure-fde-5.19 | Ubuntu | upstream | * |
Linux-azure-fde-6.2 | Ubuntu | jammy | * |
Linux-azure-fde-6.2 | Ubuntu | upstream | * |
Linux-azure-fips | Ubuntu | upstream | * |
Linux-bluefield | Ubuntu | upstream | * |
Linux-fips | Ubuntu | upstream | * |
Linux-gcp | Ubuntu | esm-infra/bionic | * |
Linux-gcp | Ubuntu | upstream | * |
Linux-gcp-4.15 | Ubuntu | upstream | * |
Linux-gcp-5.11 | Ubuntu | focal | * |
Linux-gcp-5.11 | Ubuntu | upstream | * |
Linux-gcp-5.13 | Ubuntu | focal | * |
Linux-gcp-5.13 | Ubuntu | upstream | * |
Linux-gcp-5.15 | Ubuntu | upstream | * |
Linux-gcp-5.19 | Ubuntu | jammy | * |
Linux-gcp-5.19 | Ubuntu | upstream | * |
Linux-gcp-5.3 | Ubuntu | esm-infra/bionic | * |
Linux-gcp-5.3 | Ubuntu | upstream | * |
Linux-gcp-5.4 | Ubuntu | upstream | * |
Linux-gcp-5.8 | Ubuntu | focal | * |
Linux-gcp-5.8 | Ubuntu | upstream | * |
Linux-gcp-6.2 | Ubuntu | jammy | * |
Linux-gcp-6.2 | Ubuntu | upstream | * |
Linux-gcp-6.5 | Ubuntu | upstream | * |
Linux-gcp-fips | Ubuntu | upstream | * |
Linux-gke | Ubuntu | focal | * |
Linux-gke | Ubuntu | upstream | * |
Linux-gke-4.15 | Ubuntu | esm-infra/bionic | * |
Linux-gke-4.15 | Ubuntu | upstream | * |
Linux-gke-5.15 | Ubuntu | focal | * |
Linux-gke-5.15 | Ubuntu | upstream | * |
Linux-gke-5.4 | Ubuntu | esm-infra/bionic | * |
Linux-gke-5.4 | Ubuntu | upstream | * |
Linux-gkeop | Ubuntu | upstream | * |
Linux-gkeop-5.15 | Ubuntu | upstream | * |
Linux-gkeop-5.4 | Ubuntu | esm-infra/bionic | * |
Linux-gkeop-5.4 | Ubuntu | upstream | * |
Linux-hwe | Ubuntu | esm-infra/bionic | * |
Linux-hwe | Ubuntu | upstream | * |
Linux-hwe-5.11 | Ubuntu | focal | * |
Linux-hwe-5.11 | Ubuntu | upstream | * |
Linux-hwe-5.13 | Ubuntu | focal | * |
Linux-hwe-5.13 | Ubuntu | upstream | * |
Linux-hwe-5.15 | Ubuntu | upstream | * |
Linux-hwe-5.19 | Ubuntu | jammy | * |
Linux-hwe-5.19 | Ubuntu | upstream | * |
Linux-hwe-5.4 | Ubuntu | upstream | * |
Linux-hwe-5.8 | Ubuntu | focal | * |
Linux-hwe-5.8 | Ubuntu | upstream | * |
Linux-hwe-6.2 | Ubuntu | jammy | * |
Linux-hwe-6.2 | Ubuntu | upstream | * |
Linux-hwe-6.5 | Ubuntu | upstream | * |
Linux-hwe-edge | Ubuntu | esm-infra/bionic | * |
Linux-hwe-edge | Ubuntu | esm-infra/xenial | * |
Linux-hwe-edge | Ubuntu | upstream | * |
Linux-ibm | Ubuntu | mantic | * |
Linux-ibm | Ubuntu | upstream | * |
Linux-ibm-5.15 | Ubuntu | upstream | * |
Linux-ibm-5.4 | Ubuntu | upstream | * |
Linux-intel | Ubuntu | upstream | * |
Linux-intel-5.13 | Ubuntu | focal | * |
Linux-intel-5.13 | Ubuntu | upstream | * |
Linux-intel-iotg | Ubuntu | upstream | * |
Linux-intel-iotg-5.15 | Ubuntu | upstream | * |
Linux-iot | Ubuntu | upstream | * |
Linux-kvm | Ubuntu | upstream | * |
Linux-laptop | Ubuntu | upstream | * |
Linux-lowlatency | Ubuntu | upstream | * |
Linux-lowlatency-hwe-5.15 | Ubuntu | upstream | * |
Linux-lowlatency-hwe-5.19 | Ubuntu | jammy | * |
Linux-lowlatency-hwe-5.19 | Ubuntu | upstream | * |
Linux-lowlatency-hwe-6.2 | Ubuntu | jammy | * |
Linux-lowlatency-hwe-6.2 | Ubuntu | upstream | * |
Linux-lowlatency-hwe-6.5 | Ubuntu | upstream | * |
Linux-lts-xenial | Ubuntu | upstream | * |
Linux-nvidia | Ubuntu | upstream | * |
Linux-nvidia-6.2 | Ubuntu | jammy | * |
Linux-nvidia-6.2 | Ubuntu | upstream | * |
Linux-nvidia-6.5 | Ubuntu | upstream | * |
Linux-oem | Ubuntu | esm-infra/bionic | * |
Linux-oem | Ubuntu | upstream | * |
Linux-oem-5.10 | Ubuntu | focal | * |
Linux-oem-5.10 | Ubuntu | upstream | * |
Linux-oem-5.13 | Ubuntu | focal | * |
Linux-oem-5.13 | Ubuntu | upstream | * |
Linux-oem-5.14 | Ubuntu | focal | * |
Linux-oem-5.14 | Ubuntu | upstream | * |
Linux-oem-5.17 | Ubuntu | jammy | * |
Linux-oem-5.17 | Ubuntu | upstream | * |
Linux-oem-5.6 | Ubuntu | focal | * |
Linux-oem-5.6 | Ubuntu | upstream | * |
Linux-oem-6.0 | Ubuntu | jammy | * |
Linux-oem-6.0 | Ubuntu | upstream | * |
Linux-oem-6.1 | Ubuntu | jammy | * |
Linux-oem-6.1 | Ubuntu | upstream | * |
Linux-oem-6.5 | Ubuntu | upstream | * |
Linux-oem-6.8 | Ubuntu | upstream | * |
Linux-oracle | Ubuntu | upstream | * |
Linux-oracle-5.0 | Ubuntu | esm-infra/bionic | * |
Linux-oracle-5.0 | Ubuntu | upstream | * |
Linux-oracle-5.11 | Ubuntu | focal | * |
Linux-oracle-5.11 | Ubuntu | upstream | * |
Linux-oracle-5.13 | Ubuntu | focal | * |
Linux-oracle-5.13 | Ubuntu | upstream | * |
Linux-oracle-5.15 | Ubuntu | upstream | * |
Linux-oracle-5.3 | Ubuntu | esm-infra/bionic | * |
Linux-oracle-5.3 | Ubuntu | upstream | * |
Linux-oracle-5.4 | Ubuntu | upstream | * |
Linux-oracle-5.8 | Ubuntu | focal | * |
Linux-oracle-5.8 | Ubuntu | upstream | * |
Linux-oracle-6.5 | Ubuntu | upstream | * |
Linux-raspi | Ubuntu | upstream | * |
Linux-raspi-5.4 | Ubuntu | upstream | * |
Linux-raspi2 | Ubuntu | focal | * |
Linux-raspi2 | Ubuntu | upstream | * |
Linux-riscv | Ubuntu | focal | * |
Linux-riscv | Ubuntu | jammy | * |
Linux-riscv | Ubuntu | upstream | * |
Linux-riscv-5.11 | Ubuntu | focal | * |
Linux-riscv-5.11 | Ubuntu | upstream | * |
Linux-riscv-5.15 | Ubuntu | upstream | * |
Linux-riscv-5.19 | Ubuntu | jammy | * |
Linux-riscv-5.19 | Ubuntu | upstream | * |
Linux-riscv-5.8 | Ubuntu | focal | * |
Linux-riscv-5.8 | Ubuntu | upstream | * |
Linux-riscv-6.5 | Ubuntu | upstream | * |
Linux-starfive | Ubuntu | upstream | * |
Linux-starfive-5.19 | Ubuntu | jammy | * |
Linux-starfive-5.19 | Ubuntu | upstream | * |
Linux-starfive-6.2 | Ubuntu | jammy | * |
Linux-starfive-6.2 | Ubuntu | upstream | * |
Linux-starfive-6.5 | Ubuntu | upstream | * |
Linux-xilinx-zynqmp | Ubuntu | upstream | * |