2022-06-08 04:43:56

by Xiaohui Zhang

Subject: [PATCH 1/1] cxgbit_target: Reject immediate data underflow larger than SCSI transfer length

Similar to the handling of iscsit_get_immediate_data in commit abb85a9b512e
("iscsi-target: Reject immediate data underflow larger than SCSI transfer length"),
we thought a patch might be needed here as well.

Signed-off-by: Xiaohui Zhang <[email protected]>
---
drivers/target/iscsi/cxgbit/cxgbit_target.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/target/iscsi/cxgbit/cxgbit_target.c b/drivers/target/iscsi/cxgbit/cxgbit_target.c
index acfc39683c87..800bec4b1e88 100644
--- a/drivers/target/iscsi/cxgbit/cxgbit_target.c
+++ b/drivers/target/iscsi/cxgbit/cxgbit_target.c
@@ -920,6 +920,18 @@ cxgbit_get_immediate_data(struct iscsit_cmd *cmd, struct iscsi_scsi_req *hdr,
*/
if (dump_payload)
goto after_immediate_data;
+ /*
+ * Check for underflow case where both EDTL and immediate data payload
+ * exceeds what is presented by CDB's TRANSFER LENGTH, and what has
+ * already been set in target_cmd_size_check() as se_cmd->data_length.
+ *
+ * For this special case, fail the command and dump the immediate data
+ * payload.
+ */
+ if (cmd->first_burst_len > cmd->se_cmd.data_length) {
+ cmd->sense_reason = TCM_INVALID_CDB_FIELD;
+ goto after_immediate_data;
+ }

immed_ret = cxgbit_handle_immediate_data(cmd, hdr,
cmd->first_burst_len);
--
2.17.1

2022-06-08 05:08:47

by Mike Christie

Subject: Re: [PATCH 1/1] cxgbit_target: Reject immediate data underflow larger than SCSI transfer length

On 6/7/22 9:30 AM, Xiaohui Zhang wrote:
> Similar to the handling of iscsit_get_immediate_data in commit abb85a9b512e
> ("iscsi-target: Reject immediate data underflow larger than SCSI transfer length"),
> we thought a patch might be needed here as well.
>
> Signed-off-by: Xiaohui Zhang <[email protected]>
> ---
> drivers/target/iscsi/cxgbit/cxgbit_target.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/target/iscsi/cxgbit/cxgbit_target.c b/drivers/target/iscsi/cxgbit/cxgbit_target.c
> index acfc39683c87..800bec4b1e88 100644
> --- a/drivers/target/iscsi/cxgbit/cxgbit_target.c
> +++ b/drivers/target/iscsi/cxgbit/cxgbit_target.c
> @@ -920,6 +920,18 @@ cxgbit_get_immediate_data(struct iscsit_cmd *cmd, struct iscsi_scsi_req *hdr,
> */
> if (dump_payload)
> goto after_immediate_data;
> + /*
> + * Check for underflow case where both EDTL and immediate data payload
> + * exceeds what is presented by CDB's TRANSFER LENGTH, and what has
> + * already been set in target_cmd_size_check() as se_cmd->data_length.
> + *
> + * For this special case, fail the command and dump the immediate data
> + * payload.
> + */
> + if (cmd->first_burst_len > cmd->se_cmd.data_length) {
> + cmd->sense_reason = TCM_INVALID_CDB_FIELD;
> + goto after_immediate_data;
> + }
>

Do you need something like Bart's patch:

commit 4b3766ec0e1840f45bc9238e7e749922bdcb7016
Author: Bart Van Assche <[email protected]>
Date: Tue Apr 2 12:58:15 2019 -0700

scsi: target/iscsi: Make sure PDU processing continues if parsing a command fails

with your patch or does cxgb avoid that somehow?