scsi: fcoe: fix use-after-free in fcoe_ctlr_els_send

KASAN reports a use-after-free in fcoe_ctlr_els_send() when we're sending a
LOGO and have FIP debugging enabled. This is because we're first freeing
the skb and then printing the frame's DID. But the DID is a member of the
FC frame header which in turn is the skb's payload.

Exchange the debug print and kfree_skb() calls so we're not touching the
freed data.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Johannes Thumshirn 2018-07-31 15:46:01 +02:00 committed by Martin K. Petersen
parent 15d258674b
commit 2d7d4fd35e
1 changed files with 1 additions and 1 deletions

View File

@ -799,9 +799,9 @@ int fcoe_ctlr_els_send(struct fcoe_ctlr *fip, struct fc_lport *lport,
fip->send(fip, skb);
return -EINPROGRESS;
drop:
kfree_skb(skb);
LIBFCOE_FIP_DBG(fip, "drop els_send op %u d_id %x\n",
op, ntoh24(fh->fh_d_id));
kfree_skb(skb);
return -EINVAL;
}
EXPORT_SYMBOL(fcoe_ctlr_els_send);