Re: [PATCH] scsi: qla2xxx: avoid crash in qlt_handle_abts_completion() if mcmd == NULL

[Lee Duncan]

On 11/4/19 10:18 AM, Thomas Abraham wrote:
> qlt_ctio_to_cmd() will return a NULL mcmd if h == QLA_TGT_SKIP_HANDLE. If
> the error subcodes don't match the exact codes checked a crash will occur
> when calling free_mcmd on the null mcmd
> 
> Signed-off-by: Thomas Abraham <tabraham@xxxxxxxx>
> ---
>  drivers/scsi/qla2xxx/qla_target.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/qla2xxx/qla_target.c b/drivers/scsi/qla2xxx/qla_target.c
> index a06e56224a55..611ab224662f 100644
> --- a/drivers/scsi/qla2xxx/qla_target.c
> +++ b/drivers/scsi/qla2xxx/qla_target.c
> @@ -5732,7 +5732,8 @@ static void qlt_handle_abts_completion(struct scsi_qla_host *vha,
>  			    vha->vp_idx, entry->compl_status,
>  			    entry->error_subcode1,
>  			    entry->error_subcode2);
> -			ha->tgt.tgt_ops->free_mcmd(mcmd);
> +			if (mcmd)
> +				ha->tgt.tgt_ops->free_mcmd(mcmd);
>  		}
>  	} else if (mcmd) {
>  		ha->tgt.tgt_ops->free_mcmd(mcmd);
> 

Reviewed-by: Lee Duncan <lduncan@xxxxxxxx>