When cmdid == CMDID_INT_CMDS, the 'mbox' pointer is NULL but is
dereferenced below.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 0f2bb84d2a68 ("[SCSI] megaraid: simplify internal command handling")
Signed-off-by: Igor Artemiev <[email protected]>
---
drivers/scsi/megaraid.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index bf491af9f0d6..4fbf92dc717e 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -1441,6 +1441,7 @@ mega_cmd_done(adapter_t *adapter, u8 completed[], int nstatus, int status)
*/
if (cmdid == CMDID_INT_CMDS) {
scb = &adapter->int_scb;
+ mbox = (mbox_t *)scb->raw_mbox;
list_del_init(&scb->list);
scb->state = SCB_FREE;
--
2.30.2
On Mon, 2023-04-03 at 17:34 +0300, Igor Artemiev wrote:
> When cmdid == CMDID_INT_CMDS, the 'mbox' pointer is NULL but is
> dereferenced below.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: 0f2bb84d2a68 ("[SCSI] megaraid: simplify internal command
> handling")
> Signed-off-by: Igor Artemiev <[email protected]>
> ---
> drivers/scsi/megaraid.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
> index bf491af9f0d6..4fbf92dc717e 100644
> --- a/drivers/scsi/megaraid.c
> +++ b/drivers/scsi/megaraid.c
> @@ -1441,6 +1441,7 @@ mega_cmd_done(adapter_t *adapter, u8
> completed[], int nstatus, int status)
> */
> if (cmdid == CMDID_INT_CMDS) {
> scb = &adapter->int_scb;
> + mbox = (mbox_t *)scb->raw_mbox;
Have you actually seen this and if so which firmware? I thought
megaraid internal commands only ever returned success or fail (0 or 1)
meaning they can never get into the sense processing case that is the
only consumer of the mbox.
James
On 4/3/23 18:19, James Bottomley wrote:
> On Mon, 2023-04-03 at 17:34 +0300, Igor Artemiev wrote:
>> When cmdid == CMDID_INT_CMDS, the 'mbox' pointer is NULL but is
>> dereferenced below.
>>
>> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>>
>> Fixes: 0f2bb84d2a68 ("[SCSI] megaraid: simplify internal command
>> handling")
>> Signed-off-by: Igor Artemiev <[email protected]>
>> ---
>> drivers/scsi/megaraid.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
>> index bf491af9f0d6..4fbf92dc717e 100644
>> --- a/drivers/scsi/megaraid.c
>> +++ b/drivers/scsi/megaraid.c
>> @@ -1441,6 +1441,7 @@ mega_cmd_done(adapter_t *adapter, u8
>> completed[], int nstatus, int status)
>> */
>> if (cmdid == CMDID_INT_CMDS) {
>> scb = &adapter->int_scb;
>> + mbox = (mbox_t *)scb->raw_mbox;
> Have you actually seen this and if so which firmware? I thought
> megaraid internal commands only ever returned success or fail (0 or 1)
> meaning they can never get into the sense processing case that is the
> only consumer of the mbox.
>
> James
>
No, I haven't seen this. A null dereference can be if the 'status' is
0x02. But if 'status' cannot be equal to 0x02, assignment isn't required.
Thanks,
Igor