[PATCH 3.16 34/61] scsi: sg: fixup infoleak when using SG_GET_REQUEST_TABLE

[Ben Hutchings]

3.16.85-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Hannes Reinecke <hare@xxxxxxx>

commit 3e0097499839e0fe3af380410eababe5a47c4cf9 upstream.

When calling SG_GET_REQUEST_TABLE ioctl only a half-filled table is
returned; the remaining part will then contain stale kernel memory
information.  This patch zeroes out the entire table to avoid this
issue.

Signed-off-by: Hannes Reinecke <hare@xxxxxxxx>
Reviewed-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/scsi/sg.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -881,7 +881,6 @@ sg_fill_request_table(Sg_fd *sfp, sg_req
 	list_for_each_entry(srp, &sfp->rq_list, entry) {
 		if (val > SG_MAX_QUEUE)
 			break;
-		memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 		rinfo[val].req_state = srp->done + 1;
 		rinfo[val].problem =
 			srp->header.masked_status &
@@ -1098,8 +1097,8 @@ sg_ioctl(struct file *filp, unsigned int
 		else {
 			sg_req_info_t *rinfo;
 
-			rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
-								GFP_KERNEL);
+			rinfo = kzalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
+					GFP_KERNEL);
 			if (!rinfo)
 				return -ENOMEM;
 			read_lock_irqsave(&sfp->rq_list_lock, iflags);