CVE-2024-35971net: ks8851: Handle softirqs at the end of IRQ thread to fix hang
- 7.5HighCVSS base score
- 0.69%Exploitation in 30 daysEPSS · top 47% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: net: ks8851: Handle softirqs at the end of IRQ thread to fix hang The ks8851_irq() thread may call ks8851_rx_pkts() in case there are any packets in the MAC FIFO, which calls netif_rx(). This netif_rx() implementation is guarded by local_bh_disable() and local_bh_enable(). The local_bh_enable() may call do_softirq() to run softirqs in case any are pending. One of the softirqs is net_rx_action, which ultimately reaches the driver .start_xmit callback. If that happens, the system hangs. The entire call chain is below: ks8851_start_xmit_par from netdev_start_xmit netdev_start_xmit from dev_hard_start_xmit dev_hard_start_xmit from sch_direct_xmit sch_direct_xmit from __dev_queue_xmit __dev_queue_xmit from __neigh_update __neigh_update from neigh_update neigh_update from arp_process.constprop.0 arp_process.constprop.0 from __netif_receive_skb_one_core __netif_receive_skb_one_core from process_backlog process_backlog from __napi_poll.constprop.0 __napi_poll.constprop.0 from net_rx_action net_rx_action from __do_softirq __do_softirq from call_with_stack call_with_stack from do_softirq do_softirq from __local_bh_enable_ip __local_bh_enable_ip from netif_rx netif_rx from ks8851_irq ks8851_irq from irq_thread_fn irq_thread_fn from irq_thread irq_thread from kthread kthread from ret_from_fork The hang happens because ks8851_irq() first locks a spinlock in ks8851_par.c ks8851_lock_par() spin_lock_irqsave(&ksp->lock, ...) and with that spinlock locked, calls netif_rx(). Once the execution reaches ks8851_start_xmit_par(), it calls ks8851_lock_par() again which attempts to claim the already locked spinlock again, and the hang happens. Move the do_softirq() call outside of the spinlock protected section of ks8851_irq() by disabling BHs around the entire spinlock protected section of ks8851_irq() handler. Place local_bh_enable() outside of the spinlock protected section, so that it can trigger do_softirq() without the ks8851_par.c ks8851_lock_par() spinlock being held, and safely call ks8851_start_xmit_par() without attempting to lock the already locked spinlock. Since ks8851_irq() is protected by local_bh_disable()/local_bh_enable() now, replace netif_rx() with __netif_rx() which is not duplicating the local_bh_disable()/local_bh_enable() calls.
Timeline
ID reserved
By Linux
- 3 days later
· 3 days later
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.69% · top 47% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
- affected 797047f875b5463719cc70ba213eb691d453c946 – < 492337a4fbd1421b42df684ee9b34be2a2722540
- affected 797047f875b5463719cc70ba213eb691d453c946 – < cba376eb036c2c20077b41d47b317d8218fe754f
- affected 797047f875b5463719cc70ba213eb691d453c946 – < 49d5d70538b6b8f2a3f8f1ac30c1f921d4a0929b
- affected 797047f875b5463719cc70ba213eb691d453c946 – < be0384bf599cf1eb8d337517feeb732d71f75a6f
- affected 5.8
- unaffected < 5.8
- unaffected 6.1.87 – ≤ 6.1.*
- unaffected 6.6.28 – ≤ 6.6.*
- unaffected 6.8.7 – ≤ 6.8.*
- unaffected 6.9 – ≤ *
References
References6
- https://git.kernel.org/stable/c/492337a4fbd1421b42df684ee9b34be2a2722540 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/cba376eb036c2c20077b41d47b317d8218fe754f (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/49d5d70538b6b8f2a3f8f1ac30c1f921d4a0929b (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/be0384bf599cf1eb8d337517feeb732d71f75a6f (opens in a new tab)x_transferred
- http://www.openwall.com/lists/oss-security/2024/05/30/2 (opens in a new tab)x_transferred
- http://www.openwall.com/lists/oss-security/2024/05/30/1 (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2024-35689 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2024-35971)Record last updated .