Re: [PATCH v4 3/5] nvme: refactor nvme_submit_user_cmd()

Jens Axboe
2022-05-05T19:31:41Z

On 5/5/22 1:30 PM, Clay Mayers wrote:
>> This might be better, though you'd only notice if you had integrity
>> enabled. Christoph, I'm folding this in with patch 3...
>>
>>
>> diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
>> index 8fe7ad18a709..3d827789b536 100644
>> --- a/drivers/nvme/host/ioctl.c
>> +++ b/drivers/nvme/host/ioctl.c
>> @@ -21,9 +21,13 @@ static void __user *nvme_to_user_ptr(uintptr_t ptrval)
>>
>> static inline void *nvme_meta_from_bio(struct bio *bio)
>> {
>> - struct bio_integrity_payload *bip = bio_integrity(bio);
>> + if (bio) {
>> + struct bio_integrity_payload *bip = bio_integrity(bio);
>>
>> - return bip ? bvec_virt(bip->bip_vec) : NULL;
>> + return bip ? bvec_virt(bip->bip_vec) : NULL;
>> + }
>> +
>> + return NULL;
>> }
>>
>> /*
>> @@ -205,19 +209,20 @@ static int nvme_execute_user_rq(struct request *req,
>> void __user *meta_buffer,
>> unsigned meta_len, u64 *result)
>> {
>> struct bio *bio = req->bio;
>> - bool write = bio_op(bio) == REQ_OP_DRV_OUT;
>> - int ret;
>> void *meta = nvme_meta_from_bio(bio);
>> + int ret;
>>
>> ret = nvme_execute_passthru_rq(req);
>>
>> if (result)
>> *result = le64_to_cpu(nvme_req(req)->result.u64);
>> - if (meta && !ret && !write) {
>> - if (copy_to_user(meta_buffer, meta, meta_len))
>> + if (meta) {
>> + bool write = bio_op(bio) == REQ_OP_DRV_OUT;
>> +
>> + if (!ret && !write && copy_to_user(meta_buffer, meta,
>> meta_len))
>> ret = -EFAULT;
>> + kfree(meta);
>> }
>> - kfree(meta);
>> if (bio)
>> blk_rq_unmap_user(bio);
>> blk_mq_free_request(req);
>>
>> --
>> Jens Axboe
>
> This does work and got me past the null ptr segfault.

OK good, thanks for testing. I did fold it in.

--
Jens Axboe