diff mbox series

[v1,2/2] s390x: Fix SCLP return code when buffer too small

Message ID 1569497622-12496-3-git-send-email-imbrenda@linux.ibm.com
State New
Headers show
Series s390x: SCLP error cleanup | expand

Commit Message

Claudio Imbrenda Sept. 26, 2019, 11:33 a.m. UTC
Return the correct error code when the SCCB buffer is too small to
contain all of the output, for the Read SCP Information and
Read CPU Information commands.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
---
 hw/s390x/sclp.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

Comments

Thomas Huth Sept. 26, 2019, 12:20 p.m. UTC | #1
On 26/09/2019 13.33, Claudio Imbrenda wrote:
> Return the correct error code when the SCCB buffer is too small to
> contain all of the output, for the Read SCP Information and
> Read CPU Information commands.
> 
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
> ---
>  hw/s390x/sclp.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
> index 76feac8..8f7fe1c 100644
> --- a/hw/s390x/sclp.c
> +++ b/hw/s390x/sclp.c
> @@ -68,6 +68,11 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
>  
>      read_info->ibc_val = cpu_to_be32(s390_get_ibc_val());
>  
> +    if (sccb->h.length < (sizeof(ReadInfo) + cpu_count * sizeof(CPUEntry))) {

Don't you need a cpu16_to_cpu() around sccb->h.length?

> +        sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
> +        return;
> +    }
> +
>      /* Configuration Characteristic (Extension) */
>      s390_get_feat_block(S390_FEAT_TYPE_SCLP_CONF_CHAR,
>                           read_info->conf_char);
> @@ -118,6 +123,11 @@ static void sclp_read_cpu_info(SCLPDevice *sclp, SCCB *sccb)
>      cpu_info->offset_configured = cpu_to_be16(offsetof(ReadCpuInfo, entries));
>      cpu_info->nr_standby = cpu_to_be16(0);
>  
> +    if (sccb->h.length < (sizeof(ReadCpuInfo) + cpu_count * sizeof(CPUEntry))) {

dito?

> +        sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
> +        return;
> +    }
> +
>      /* The standby offset is 16-byte for each CPU */
>      cpu_info->offset_standby = cpu_to_be16(cpu_info->offset_configured
>          + cpu_info->nr_configured*sizeof(CPUEntry));
> 

 Thomas
Thomas Huth Sept. 26, 2019, 12:26 p.m. UTC | #2
On 26/09/2019 14.20, Thomas Huth wrote:
> On 26/09/2019 13.33, Claudio Imbrenda wrote:
>> Return the correct error code when the SCCB buffer is too small to
>> contain all of the output, for the Read SCP Information and
>> Read CPU Information commands.
>>
>> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
>> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
>> ---
>>  hw/s390x/sclp.c | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
>> index 76feac8..8f7fe1c 100644
>> --- a/hw/s390x/sclp.c
>> +++ b/hw/s390x/sclp.c
>> @@ -68,6 +68,11 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
>>  
>>      read_info->ibc_val = cpu_to_be32(s390_get_ibc_val());
>>  
>> +    if (sccb->h.length < (sizeof(ReadInfo) + cpu_count * sizeof(CPUEntry))) {
> 
> Don't you need a cpu16_to_cpu() around sccb->h.length?

I meant be16_to_cpu(), obviously.

 Thomas
diff mbox series

Patch

diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index 76feac8..8f7fe1c 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -68,6 +68,11 @@  static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
 
     read_info->ibc_val = cpu_to_be32(s390_get_ibc_val());
 
+    if (sccb->h.length < (sizeof(ReadInfo) + cpu_count * sizeof(CPUEntry))) {
+        sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
+        return;
+    }
+
     /* Configuration Characteristic (Extension) */
     s390_get_feat_block(S390_FEAT_TYPE_SCLP_CONF_CHAR,
                          read_info->conf_char);
@@ -118,6 +123,11 @@  static void sclp_read_cpu_info(SCLPDevice *sclp, SCCB *sccb)
     cpu_info->offset_configured = cpu_to_be16(offsetof(ReadCpuInfo, entries));
     cpu_info->nr_standby = cpu_to_be16(0);
 
+    if (sccb->h.length < (sizeof(ReadCpuInfo) + cpu_count * sizeof(CPUEntry))) {
+        sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH);
+        return;
+    }
+
     /* The standby offset is 16-byte for each CPU */
     cpu_info->offset_standby = cpu_to_be16(cpu_info->offset_configured
         + cpu_info->nr_configured*sizeof(CPUEntry));