[PATCH 4.9 49/77] scsi: sg: off by one in sg_ioctl()

From: Greg Kroah-Hartman
Date: Sun Sep 24 2017 - 16:38:50 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit bd46fc406b30d1db1aff8dabaff8d18bb423fdcf upstream.

If "val" is SG_MAX_QUEUE then we are one element beyond the end of the
"rinfo" array so the > should be >=.

Fixes: 109bade9c625 ("scsi: sg: use standard lists for sg_requests")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Douglas Gilbert <dgilbert@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/scsi/sg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1031,7 +1031,7 @@ sg_ioctl(struct file *filp, unsigned int
read_lock_irqsave(&sfp->rq_list_lock, iflags);
val = 0;
list_for_each_entry(srp, &sfp->rq_list, entry) {
- if (val > SG_MAX_QUEUE)
+ if (val >= SG_MAX_QUEUE)
break;
memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
rinfo[val].req_state = srp->done + 1;