Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Cc:     harshit.m.mogalapalli@oracle.com, error27@gmail.com,
        harshit.m.mogalapalli@gmail.com,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Hannes Reinecke <hare@suse.de>,
        Douglas Gilbert <dgilbert@interlog.com>,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] scsi: scsi_debug: Fix a warning in resp_verify()
Date:   Fri, 11 Nov 2022 23:00:31 -0800
Message-Id: <20221112070031.2121068-1-harshit.m.mogalapalli@oracle.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
To:     unlisted-recipients:; (no To-header on input)
Precedence: bulk

As 'vnum' is controlled by user, so 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: c3e2fe9222d4 ("scsi: scsi_debug: Implement VERIFY(10), add VERIFY(16)")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
---
 drivers/scsi/scsi_debug.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 697fc57bc711..cbb9395c90c1 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -4429,7 +4429,7 @@ static int resp_verify(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 	if (ret)
 		return ret;
 
-	arr = kcalloc(lb_size, vnum, GFP_ATOMIC);
+	arr = kcalloc(lb_size, vnum, GFP_ATOMIC | __GFP_NOWARN);
 	if (!arr) {
 		mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
 				INSUFF_RES_ASCQ);
-- 
2.38.1