| Message ID | 20221111100526.1790533-1-harshit.m.mogalapalli@oracle.com |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: scsi_debug: Fix a warning in resp_write_scat() | expand |
On Fri, 11 Nov 2022 02:05:25 -0800, Harshit Mogalapalli wrote: > As 'lbdof_blen' is coming from user, if the size in kzalloc() > is >= MAX_ORDER then we hit a warning. > > Call trace: > > sg_ioctl > sg_ioctl_common > scsi_ioctl > sg_scsi_ioctl > blk_execute_rq > blk_mq_sched_insert_request > blk_mq_run_hw_queue > __blk_mq_delay_run_hw_queue > __blk_mq_run_hw_queue > blk_mq_sched_dispatch_requests > __blk_mq_sched_dispatch_requests > blk_mq_dispatch_rq_list > scsi_queue_rq > scsi_dispatch_cmd > scsi_debug_queuecommand > schedule_resp > resp_write_scat > > [...] Applied to 6.2/scsi-queue, thanks! [1/1] scsi: scsi_debug: Fix a warning in resp_write_scat() https://git.kernel.org/mkp/scsi/c/216e179724c1
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 697fc57bc711..273224d29ce9 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -3778,7 +3778,7 @@ static int resp_write_scat(struct scsi_cmnd *scp, mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0); return illegal_condition_result; } - lrdp = kzalloc(lbdof_blen, GFP_ATOMIC); + lrdp = kzalloc(lbdof_blen, GFP_ATOMIC | __GFP_NOWARN); if (lrdp == NULL) return SCSI_MLQUEUE_HOST_BUSY; if (sdebug_verbose)
As 'lbdof_blen' is coming from user, if the size in kzalloc() is >= MAX_ORDER then we hit a warning. Call trace: sg_ioctl sg_ioctl_common scsi_ioctl sg_scsi_ioctl blk_execute_rq blk_mq_sched_insert_request blk_mq_run_hw_queue __blk_mq_delay_run_hw_queue __blk_mq_run_hw_queue blk_mq_sched_dispatch_requests __blk_mq_sched_dispatch_requests blk_mq_dispatch_rq_list scsi_queue_rq scsi_dispatch_cmd scsi_debug_queuecommand schedule_resp resp_write_scat If you try to allocate a memory larger than(>=) MAX_ORDER, then kmalloc() will definitely fail. It creates a stack trace and messes up dmesg. The user controls the size here so if they specify a too large size it will fail. Add __GFP_NOWARN in order to avoid too large allocation warning. This is detected by static analysis using smatch. Fixes: 481b5e5c7949 ("scsi: scsi_debug: add resp_write_scat function") Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> --- drivers/scsi/scsi_debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)