Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
soc: fsl: qbman: Use raw spinlock for cgr_lock
smp_call_function always runs its callback in hard IRQ context, even on PREEMPT_RT, where spinlocks can sleep. So we need to use a raw spinlock for cgr_lock to ensure we aren’t waiting on a sleeping task.
Although this bug has existed for a while, it was not apparent until commit ef2a8d5478b9 (“net: dpaa: Adjust queue depth on rate change”) which invokes smp_call_function_single via qman_update_cgr_safe every time a link goes up or down.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS
- Affected packages:
- kernel @ 5.14.0 (+7 more)
In the Linux kernel, the following vulnerability has been resolved:
soc: fsl: qbman: Use raw spinlock for cgr_lock
smp_call_function always runs its callback in hard IRQ context, even on PREEMPT_RT, where spinlocks can sleep. So we need to use a raw spinlock for cgr_lock to ensure we aren’t waiting on a sleeping task.
Although this bug has existed for a while, it was not apparent until commit ef2a8d5478b9 (“net: dpaa: Adjust queue depth on rate change”) which invokes smp_call_function_single via qman_update_cgr_safe every time a link goes up or down.