{"cve":"CVE-2026-46031","nvd":{"published":"2026-05-27T14:17:22.057","modified":"2026-06-17T10:52:55.930","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ks8851: Reinstate disabling of BHs around IRQ handler\n\nIf the driver executes ks8851_irq() AND a TX packet has been sent, then\nthe driver enables TX queue via netif_wake_queue() which schedules TX\nsoftirq to queue packets for this device.\n\nIf CONFIG_PREEMPT_RT=y is set AND a packet has also been received by\nthe MAC, then ks8851_rx_pkts() calls netdev_alloc_skb_ip_align() to\nallocate SKBs for the received packets. If netdev_alloc_skb_ip_align()\nis called with BH enabled, then local_bh_enable() at the end of\nnetdev_alloc_skb_ip_align() will trigger the pending softirq processing,\nwhich may ultimately call the .xmit callback ks8851_start_xmit_par().\nThe ks8851_start_xmit_par() will try to lock struct ks8851_net_par\n.lock spinlock, which is already locked by ks8851_irq() from which\nks8851_start_xmit_par() was called. This leads to a deadlock, which\nis reported by the kernel, including a trace listed below.\n\nIf CONFIG_PREEMPT_RT is not set, then since commit 0913ec336a6c0\n(\"net: ks8851: Fix deadlock with the SPI chip variant\") the deadlock\ncan also be triggered without received packet in the RX FIFO. The\npending softirqs will be processed on return from\nspin_unlock_bh(&ks->statelock) in ks8851_irq(), which triggers the\ndeadlock as well.\n\nFix the problem by disabling BH around critical sections, including the\nIRQ handler, thus preventing the net_tx_action() softirq from triggering\nduring these critical sections. The net_tx_action() softirq is triggered\nonce BH are re-enabled and at the end of the IRQ handler, once all the\nother IRQ handler actions have been completed.\n\n __schedule from schedule_rtlock+0x1c/0x34\n schedule_rtlock from rtlock_slowlock_locked+0x548/0x904\n rtlock_slowlock_locked from rt_spin_lock+0x60/0x9c\n rt_spin_lock from ks8851_start_xmit_par+0x74/0x1a8\n ks8851_start_xmit_par from netdev_start_xmit+0x20/0x44\n netdev_start_xmit from dev_hard_start_xmit+0xd0/0x188\n dev_hard_start_xmit from sch_direct_xmit+0xb8/0x25c\n sch_direct_xmit from __qdisc_run+0x1f8/0x4ec\n __qdisc_run from qdisc_run+0x1c/0x28\n qdisc_run from net_tx_action+0x1f0/0x268\n net_tx_action from handle_softirqs+0x1a4/0x270\n handle_softirqs from __local_bh_enable_ip+0xcc/0xe0\n __local_bh_enable_ip from __alloc_skb+0xd8/0x128\n __alloc_skb from __netdev_alloc_skb+0x3c/0x19c\n __netdev_alloc_skb from ks8851_irq+0x388/0x4d4\n ks8851_irq from irq_thread_fn+0x24/0x64\n irq_thread_fn from irq_thread+0x178/0x28c\n irq_thread from kthread+0x12c/0x138\n kthread from ret_from_fork+0x14/0x28","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-667"],"references":["https://git.kernel.org/stable/c/1962027a6d223f90df8b372929f9d1a8d321ad6a","https://git.kernel.org/stable/c/21f1707a8e978558dcb11b053855521e32ac0eec","https://git.kernel.org/stable/c/518040324067d8efaa2da1992297b7e7bf5640f4","https://git.kernel.org/stable/c/5c9fcac3c872224316714d0d8914d9af16c76a6d","https://git.kernel.org/stable/c/640a7631d31db87d5fa1b34cea44a99b6e78854b"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:36:28.938604137+00:00"},"epss":{"cve":"CVE-2026-46031","score":0.0037,"percentile":0.30903,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}