scsi: scsi_debug: Fix a warning in resp_report_zones()

[ Upstream commit 07f2ca1 ]

As 'alloc_len' is user controlled data, if user tries to allocate memory
larger than(>=) MAX_ORDER, then kcalloc() will fail, it creates a stack
trace and messes up dmesg with a warning.

Add __GFP_NOWARN in order to avoid too large allocation warning.  This is
detected by static analysis using smatch.

Fixes: 7db0e0c ("scsi: scsi_debug: Fix buffer size of REPORT ZONES command")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20221112070612.2121535-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/scsi/scsi_debug.c

@@ -4367,7 +4367,7 @@ static int resp_report_zones(struct scsi_cmnd *scp,
 	rep_max_zones = min((alloc_len - 64) >> ilog2(RZONES_DESC_HD),
 			    max_zones);
 
-	arr = kzalloc(alloc_len, GFP_ATOMIC);
+	arr = kzalloc(alloc_len, GFP_ATOMIC | __GFP_NOWARN);
 	if (!arr) {
 		mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
 				INSUFF_RES_ASCQ);