CVE-2022-48658

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm: slub: corrige las invocaciones de flu_cpu_slab()/__free_slab() en el contexto de la tarea. Commit 5a836bf6b09f ("mm: slub: mover invocaciones de flu_cpu_slab() invocaciones de __free_slab() fuera del contexto IRQ") movió todas las invocaciones de flu_cpu_slab() a la cola de trabajo global para evitar un problema relacionado con la llamada de desactivate_slab()/__free_slab() desde un Contexto IRQ en núcleos PREEMPT_RT. Cuando se llama a la función Flush_all_cpu_locked() desde un contexto de tarea, puede suceder que una cola de trabajo con el bit WQ_MEM_RECLAIM configurado termine vaciando la cola de trabajo global, esto causará un problema de dependencia. cola de trabajo: WQ_MEM_RECLAIM nvme-delete-wq:nvme_delete_ctrl_work [nvme_core] se está vaciando! Eventos WQ_MEM_RECLAIM:flush_cpu_slab ADVERTENCIA: CPU: 37 PID: 410 en kernel/workqueue.c:2637 check_flush_dependency+0x10a/0x120 Cola de trabajo: vme-delete-wq nvme_delete_ctrl_work [ nvme_core] RIP: 0010:check_flush_dependency+0x10a/0x120[ 453.262125] Seguimiento de llamadas: __flush_work.isra.0+0xbf/0x220? __queue_work+0x1dc/0x420 Flush_all_cpus_locked+0xfb/0x120 __kmem_cache_shutdown+0x2b/0x320 kmem_cache_destroy+0x49/0x100 bioset_exit+0x143/0x190 blk_release_queue+0xb9/0x100 kobject_cleanup+0 x37/0x130 nvme_fc_ctrl_free+0xc6/0x150 [nvme_fc] nvme_free_ctrl+0x1ac/0x2b0 [nvme_core ] Corrija este error creando una cola de trabajo para la operación de vaciado con el bit WQ_MEM_RECLAIM establecido.

In the Linux kernel, the following vulnerability has been resolved: mm: slub: fix flush_cpu_slab()/__free_slab() invocations in task context. Commit 5a836bf6b09f ("mm: slub: move flush_cpu_slab() invocations __free_slab() invocations out of IRQ context") moved all flush_cpu_slab() invocations to the global workqueue to avoid a problem related with deactivate_slab()/__free_slab() being called from an IRQ context on PREEMPT_RT kernels. When the flush_all_cpu_locked() function is called from a task context it may happen that a workqueue with WQ_MEM_RECLAIM bit set ends up flushing the global workqueue, this will cause a dependency issue. workqueue: WQ_MEM_RECLAIM nvme-delete-wq:nvme_delete_ctrl_work [nvme_core] is flushing !WQ_MEM_RECLAIM events:flush_cpu_slab WARNING: CPU: 37 PID: 410 at kernel/workqueue.c:2637 check_flush_dependency+0x10a/0x120 Workqueue: nvme-delete-wq nvme_delete_ctrl_work [nvme_core] RIP: 0010:check_flush_dependency+0x10a/0x120[ 453.262125] Call Trace: __flush_work.isra.0+0xbf/0x220 ? __queue_work+0x1dc/0x420 flush_all_cpus_locked+0xfb/0x120 __kmem_cache_shutdown+0x2b/0x320 kmem_cache_destroy+0x49/0x100 bioset_exit+0x143/0x190 blk_release_queue+0xb9/0x100 kobject_cleanup+0x37/0x130 nvme_fc_ctrl_free+0xc6/0x150 [nvme_fc] nvme_free_ctrl+0x1ac/0x2b0 [nvme_core] Fix this bug by creating a workqueue for the flush operation with the WQ_MEM_RECLAIM bit set.