{
  "public_date" : "2026-05-27T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: net: ks8851: Reinstate disabling of BHs around IRQ handler",
    "id" : "2482126",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2482126"
  },
  "cwe" : "CWE-821",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnet: ks8851: Reinstate disabling of BHs around IRQ handler\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.\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.\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.\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__schedule from schedule_rtlock+0x1c/0x34\nschedule_rtlock from rtlock_slowlock_locked+0x548/0x904\nrtlock_slowlock_locked from rt_spin_lock+0x60/0x9c\nrt_spin_lock from ks8851_start_xmit_par+0x74/0x1a8\nks8851_start_xmit_par from netdev_start_xmit+0x20/0x44\nnetdev_start_xmit from dev_hard_start_xmit+0xd0/0x188\ndev_hard_start_xmit from sch_direct_xmit+0xb8/0x25c\nsch_direct_xmit from __qdisc_run+0x1f8/0x4ec\n__qdisc_run from qdisc_run+0x1c/0x28\nqdisc_run from net_tx_action+0x1f0/0x268\nnet_tx_action from handle_softirqs+0x1a4/0x270\nhandle_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\nks8851_irq from irq_thread_fn+0x24/0x64\nirq_thread_fn from irq_thread+0x178/0x28c\nirq_thread from kthread+0x12c/0x138\nkthread from ret_from_fork+0x14/0x28", "A flaw was found in the Linux kernel's ks8851 network driver. Under specific conditions related to network packet processing and interrupt handling, a race condition can occur. This vulnerability can lead to a system deadlock, causing the affected system to become unresponsive or crash." ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-46031\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-46031\nhttps://lore.kernel.org/linux-cve-announce/2026052749-CVE-2026-46031-b59b@gregkh/T" ],
  "name" : "CVE-2026-46031",
  "csaw" : false
}