CVE-2024-42071

CVE-2024-42071 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-834.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: ionic: use dev_consume_skb_any outside of napi If we're not in a NAPI softirq context, we need to be careful about how we call napi_consume_skb(), specifically we need to call it with budget==0 to signal to it that we're not in a safe context. This was found while running some configuration stress testing of traffic and a change queue config loop running, and this curious note popped out: [ 4371.402645] BUG: using smp_processor_id() in preemptible [00000000] code: ethtool/20545 [ 4371.402897] caller is napi_skb_cache_put+0x16/0x80 [ 4371.403120] CPU: 25 PID: 20545 Comm: ethtool Kdump: loaded Tainted: G OE 6.10.0-rc3-netnext+ #8 [ 4371.403302] Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 01/23/2021 [ 4371.403460] Call Trace: [ 4371.403613] <TASK> [ 4371.403758] dump_stack_lvl+0x4f/0x70 [ 4371.403904] check_preemption_disabled+0xc1/0xe0 [ 4371.404051] napi_skb_cache_put+0x16/0x80 [ 4371.404199] ionic_tx_clean+0x18a/0x240 [ionic] [ 4371.404354] ionic_tx_cq_service+0xc4/0x200 [ionic] [ 4371.404505] ionic_tx_flush+0x15/0x70 [ionic] [ 4371.404653] ? ionic_lif_qcq_deinit.isra.23+0x5b/0x70 [ionic] [ 4371.404805] ionic_txrx_deinit+0x71/0x190 [ionic] [ 4371.404956] ionic_reconfigure_queues+0x5f5/0xff0 [ionic] [ 4371.405111] ionic_set_ringparam+0x2e8/0x3e0 [ionic] [ 4371.405265] ethnl_set_rings+0x1f1/0x300 [ 4371.405418] ethnl_default_set_doit+0xbb/0x160 [ 4371.405571] genl_family_rcv_msg_doit+0xff/0x130 [...] I found that ionic_tx_clean() calls napi_consume_skb() which calls napi_skb_cache_put(), but before that last call is the note /* Zero budget indicate non-NAPI context called us, like netpoll */ and DEBUG_NET_WARN_ON_ONCE(!in_softirq()); Those are pretty big hints that we're doing it wrong. We can pass a context hint down through the calls to let ionic_tx_clean() know what we're doing so it can call napi_consume_skb() correctly.

Frequently asked questions

What is CVE-2024-42071?
In the Linux kernel, the following vulnerability has been resolved: ionic: use dev_consume_skb_any outside of napi If we're not in a NAPI softirq context, we need to be careful about how we call napi_consume_skb(), specifically we need to call it with budget==0 to signal to it that we're not in a safe context. This was found while running some configuration stress testing of traffic and a change queue config loop running, and this curious note popped out: [ 4371.402645] BUG: using smp_processor_id() in preemptible [00000000] code: ethtool/20545 [ 4371.402897] caller is napi_skb_cache_put+0x16/0x80 [ 4371.403120] CPU: 25 PID: 20545 Comm: ethtool Kdump: loaded Tainted: G OE 6.10.0-rc3-netnext+ #8 [ 4371.403302] Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 01/23/2021 [ 4371.403460] Call Trace: [ 4371.403613] <TASK> [ 4371.403758] dump_stack_lvl+0x4f/0x70 [ 4371.403904] check_preemption_disabled+0xc1/0xe0 [ 4371.404051] napi_skb_cache_put+0x16/0x80 [ 4371.404199] ionic_tx_clean+0x18a/0x240 [ionic] [ 4371.404354] ionic_tx_cq_service+0xc4/0x200 [ionic] [ 4371.404505] ionic_tx_flush+0x15/0x70 [ionic] [ 4371.404653] ? ionic_lif_qcq_deinit.isra.23+0x5b/0x70 [ionic] [ 4371.404805] ionic_txrx_deinit+0x71/0x190 [ionic] [ 4371.404956] ionic_reconfigure_queues+0x5f5/0xff0 [ionic] [ 4371.405111] ionic_set_ringparam+0x2e8/0x3e0 [ionic] [ 4371.405265] ethnl_set_rings+0x1f1/0x300 [ 4371.405418] ethnl_default_set_doit+0xbb/0x160 [ 4371.405571] genl_family_rcv_msg_doit+0xff/0x130 [...] I found that ionic_tx_clean() calls napi_consume_skb() which calls napi_skb_cache_put(), but before that last call is the note /* Zero budget indicate non-NAPI context called us, like netpoll */ and DEBUG_NET_WARN_ON_ONCE(!in_softirq()); Those are pretty big hints that we're doing it wrong. We can pass a context hint down through the calls to let ionic_tx_clean() know what we're doing so it can call napi_consume_skb() correctly.
How severe is CVE-2024-42071?
CVE-2024-42071 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-42071 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-42071?
CVE-2024-42071 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-42071?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-42071 have an EU (EUVD) identifier?
Yes. CVE-2024-42071 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-39903.
When was CVE-2024-42071 published?
CVE-2024-42071 was published on 2024-07-29 and last updated on 2026-08-04.

References

Affected products (1)

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