CVE-2025-40142 — Deadlock in Linux

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Disable bottom softirqs as part of spin_lock_irq() on PREEMPT_RT snd_pcm_group_lock_irq() acquires a spinlock_t and disables interrupts via spin_lock_irq(). This also implicitly disables the handling of softirqs such as TIMER_SOFTIRQ. On PREEMPT_RT softirqs are preemptible and spin_lock_irq() does not disable them. That means a timer can be invoked during spin_lock_irq() on the same CPU. Due to synchronisations reas…