CVE-2025-71133

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

RDMA/irdma: avoid invalid read in irdma_net_event

irdma_net_event() should not dereference anything from "neigh" (alias "ptr") until it has checked that the event is NETEVENT_NEIGH_UPDATE. Other events come with different structures pointed to by "ptr" and they may be smaller than struct neighbour.

Move the read of neigh->dev under the NETEVENT_NEIGH_UPDATE case.

The bug is mostly harmless, but it triggers KASAN on debug kernels:

BUG: KASAN: stack-out-of-bounds in irdma_net_event+0x32e/0x3b0 [irdma] Read of size 8 at addr ffffc900075e07f0 by task kworker/27:2/542554

CPU: 27 PID: 542554 Comm: kworker/27:2 Kdump: loaded Not tainted 5.14.0-630.el9.x86_64+debug #1 Hardware name: [...] Workqueue: events rt6_probe_deferred Call Trace: <IRQ> dump_stack_lvl+0x60/0xb0 print_address_description.constprop.0+0x2c/0x3f0 print_report+0xb4/0x270 kasan_report+0x92/0xc0 irdma_net_event+0x32e/0x3b0 [irdma] notifier_call_chain+0x9e/0x180 atomic_notifier_call_chain+0x5c/0x110 rt6_do_redirect+0xb91/0x1080 tcp_v6_err+0xe9b/0x13e0 icmpv6_notify+0x2b2/0x630 ndisc_redirect_rcv+0x328/0x530 icmpv6_rcv+0xc16/0x1360 ip6_protocol_deliver_rcu+0xb84/0x12e0 ip6_input_finish+0x117/0x240 ip6_input+0xc4/0x370 ipv6_rcv+0x420/0x7d0 __netif_receive_skb_one_core+0x118/0x1b0 process_backlog+0xd1/0x5d0 __napi_poll.constprop.0+0xa3/0x440 net_rx_action+0x78a/0xba0 handle_softirqs+0x2d4/0x9c0 do_softirq+0xad/0xe0 </IRQ>

The vulnerability is caused by dereferencing the ptr argument as a struct neighbour before verifying that the event type is NETEVENT_NEIGH_UPDATE. Other netevents pass different structures via ptr, which leads to out-of-bounds reads and is detected by KASAN on debug kernels. Since the incorrectly read data is not subsequently used in any functional logic, this issue typically does not result in crashes on production kernels without KASAN enabled. An attacker able to trigger crafted network events can therefore cause kernel crashes only on debug builds, resulting in denial of service on RDMA-enabled systems used for testing or validation.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.