2024-05-21 15:04:03
Linux
PUBLISHED
In the Linux kernel, the following vulnerability has been resolved: block: dont call rq_qos_ops->done_bio if the bio isnt tracked rq_qos framework is only applied on request based driver, so: 1) rq_qos_done_bio() neednt to be called for bio based driver 2) rq_qos_done_bio() neednt to be called for bio which isnt tracked, such as bios ended from error handling code. Especially in bio_endio(): 1) request queue is referred via bio->bi_bdev->bd_disk->queue, which may be gone since request queue refcount may not be held in above two cases 2) q->rq_qos may be freed in blk_cleanup_queue() when calling into __rq_qos_done_bio() Fix the potential kernel panic by not calling rq_qos_ops->done_bio if the bio isnt tracked. This way is safe because both ioc_rqos_done_bio() and blkcg_iolatency_done_bio() are nop if the bio isnt tracked.