From: Lee Duncan Date: Tue, 23 Feb 2021 13:06:24 -0800 Subject: scsi: iscsi: Restrict sessions and handles to admin capabilities Git-commit: 688e8128b7a92df982709a4137ea4588d16f24aa References: CVE-2021-27363 CVE-2021-27364 bsc#1182716 bsc#1182717 Patch-mainline: v5.12-rc2 Protect the iSCSI transport handle, available in sysfs, by requiring CAP_SYS_ADMIN to read it. Also protect the netlink socket by restricting reception of messages to ones sent with CAP_SYS_ADMIN. This disables normal users from being able to end arbitrary iSCSI sessions. Cc: stable@vger.kernel.org Reported-by: Adam Nichols Reviewed-by: Chris Leech Reviewed-by: Mike Christie Signed-off-by: Lee Duncan Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_transport_iscsi.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -128,6 +128,9 @@ show_transport_handle(struct device *dev char *buf) { struct iscsi_internal *priv = dev_to_iscsi_internal(dev); + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport)); } static DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL); @@ -3552,6 +3555,9 @@ iscsi_if_recv_msg(struct sk_buff *skb, s struct iscsi_cls_conn *conn; struct iscsi_endpoint *ep = NULL; + if (!netlink_capable(skb, CAP_SYS_ADMIN)) + return -EPERM; + if (nlh->nlmsg_type == ISCSI_UEVENT_PATH_UPDATE) *group = ISCSI_NL_GRP_UIP; else