Re: [PATCH 11/36] target: Properly set Sense Data Length of CHECK CONDITION

[Oliver Neukum <oneukum@suse.com>]

On 07.07.22 01:35, Thinh Nguyen wrote:
> CHECK CONDITION returns sense data, and sense data is minimum 8 bytes
> long plus additional sense data length in the data buffer. Don't just
> set the allocated buffer length to the cmd->scsi_sense_length and check
> the sense data for that.
> 
> See SPC4-r37 section 4.5.2.1.
> 
> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> ---
>  drivers/target/target_core_transport.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
> index bc1e4a7c4538..9734952a6228 100644
> --- a/drivers/target/target_core_transport.c
> +++ b/drivers/target/target_core_transport.c
> @@ -3459,12 +3459,20 @@ static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
>  
>  	cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
>  	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
> -	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
> +
> +	/*
> +	 * CHECK CONDITION returns sense data, and sense data is minimum 8
> +	 * bytes long. See SPC4-r37 section 4.5.2.1.
> +	 */
> +	cmd->scsi_sense_length = 8;
> +
>  	scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
>  	if (sd->add_sense_info)
>  		WARN_ON_ONCE(scsi_set_sense_information(buffer,
>  							cmd->scsi_sense_length,
>  							cmd->sense_info) < 0);
> +	/* Additional sense data length */
> +	cmd->scsi_sense_length += buffer[7];

Doesn't this need to check for overflows?

	Regards
		Oliver