scsi: scsi_debug: Fix a warning in resp_verify()

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>
Link: https://lore.kernel.org/r/20221112070031.2121068-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 273224d..f556e36 100644 (file)
--- 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);