Re: [PATCH RFC] blk-mq: fix potential uaf for 'queue_hw_ctx'

["yukuai (C)" <yukuai3@huawei.com>]

在 2022/02/25 10:40, Ming Lei 写道:

>> +static inline struct blk_mq_hw_ctx *queue_hctx(struct request_queue *q, int id)
>> +{
>> +	struct blk_mq_hw_ctx *hctx;
>> +
>> +	rcu_read_lock();
>> +	hctx = *(rcu_dereference(q->queue_hw_ctx) + id);
>> +	rcu_read_unlock();
>> +
>> +	return hctx;
>> +}
> 
> queue_hctx() should be moved into linux/blk-mq.h, otherwise feel free to
> add:
> 
> Reviewed-by: Ming Lei <ming.lei@redhat.com>

Thanks for the review, I will send a new patch and move queue_hctx.

Kuai
> 
> Also it should be fine to implement queue_for_each_hw_ctx() as list, then we
> can avoid the allocation for q->queue_hw_ctx without extra cost. I will work
> toward that direction for improving the code.
> 
> Thanks,
> Ming
> 
> .
>