Re: [PATCH] scsi: Let scsi_execute_cmd() mark args->sshdr as invalid

From: John Garry
Date: Wed May 17 2023 - 11:39:20 EST


On 17/05/2023 05:54, Juergen Gross wrote:
On 17.05.23 04:06, Martin K. Petersen wrote:

Juergen,

Some callers of scsi_execute_cmd() (like e.g. sd_spinup_disk()) are
passing an uninitialized struct sshdr and don't look at the return
value of scsi_execute_cmd() before looking at the contents of that
struct.

Which callers? sd_spinup_disk() appears to do the right thing...


Not really. It is calling media_not_present() directly after the call of
scsi_execute_cmd() without checking the result.

Is there a reason that callers of scsi_execute_cmd() are not always checking the result for a negative error code (before examining the buffer)?

media_not_present() is looking
at sshdr, which is uninitialized in case of an early error in
scsi_execute_cmd(). The same applies to read_capacity_1[06]().

scsi_test_unit_ready() and scsi_report_lun_scan() have the problem, too.

Do I need to find other examples?

Thanks,
John