PT-2026-64651 · Linux · Linux

CVE-2026-64430 · Published 2026-07-25 · Updated 2026-07-25

Mitre

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

NTB: epf: Avoid calling pci irq vector() from hardirq context

ntb epf vec isr() calls pci irq vector() in hardirq context to derive the vector number. pci irq vector() calls msi get virq() that takes a mutex and can therefore trigger "scheduling while atomic" splats:

BUG: scheduling while atomic: kworker/u33:0/55/0x00010001 ... Call trace: ... schedule+0x38/0x110 schedule preempt disabled+0x28/0x50 mutex lock.constprop.0+0x848/0x908 mutex lock slowpath+0x18/0x30 mutex lock+0x4c/0x60 msi domain get virq+0xe8/0x138 pci irq vector+0x2c/0x60 ntb epf vec isr+0x28/0x120 [ntb hw epf] handle irq event percpu+0x70/0x3a8 handle irq event+0x48/0x100 handle edge irq+0x100/0x1c8 ...

Cache the Linux IRQ number for vector 0 when vectors are allocated and use it as a base in the ISR. Running the ISR in a threaded IRQ handler would also avoid the problem, but that would be unnecessary here.

Related Identifiers

CVE-2026-64430

Affected Products

Linux

References · 8

• https://nvd.nist.gov/vuln/detail/CVE-2026-64430 · Security Note
• https://git.kernel.org/stable/c/4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f · Note
• https://git.kernel.org/stable/c/f71e8d9875069fa73e335f63f02ec6e52e3aaa51 · Note
• https://git.kernel.org/stable/c/33bba331a4a5fee8b6026fe72eca13cceeec1b7b · Note
• https://git.kernel.org/stable/c/1dba8444ac0100133d72374634f6d7451fff1ccc · Note
• https://git.kernel.org/stable/c/6350df503897d57c5634f71b0767d48c3b837583 · Note
• https://git.kernel.org/stable/c/174a97f21bf9c54fa37ec0f321692e862ea130a3 · Note
• https://git.kernel.org/stable/c/aff271b12a1eb8c8b3da19223ae1a6abe1e8168b · Note