Re: [PATCH] scsi: sr: Fix a potential uninit-value in sr_get_events()

From: Shigeru Yoshida
Date: Mon Oct 30 2023 - 04:14:12 EST


On Wed, 31 May 2023 15:44:17 -0700, Bart Van Assche wrote:
> On 5/31/23 09:43, Shigeru Yoshida wrote:
>> diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
>> index 12869e6d4ebd..86b43c069a44 100644
>> --- a/drivers/scsi/sr.c
>> +++ b/drivers/scsi/sr.c
>> @@ -177,10 +177,13 @@ static unsigned int sr_get_events(struct
>> scsi_device *sdev)
>> result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, buf, sizeof(buf),
>> SR_TIMEOUT, MAX_RETRIES, &exec_args);
>> + if (result)
>> + return 0;
>> +
>> if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION)
>> return DISK_EVENT_MEDIA_CHANGE;
>> - if (result || be16_to_cpu(eh->data_len) < sizeof(*med))
>> + if (be16_to_cpu(eh->data_len) < sizeof(*med))
>> return 0;
>
> I think this change is wrong because it introduces an unintended
> behavior
> change. A better solution is probably to zero-initialize sshdr before
> scsi_execute_cmd() is called.

Hi Bart,

I'm very sorry for the very late response, and thank you so much for
your feedback. I'll prepare the v2 patch as you suggested.

Thanks,
Shigeru

>
> Thanks,
>
> Bart.
>