qubes-linux-kernel/patches.xen/8fe5ab411209-xen-xenbus_dev_frontend-Verify-body-of-XS_TRANSACTIO.patch
2018-04-16 23:21:01 +02:00

56 lines
2.0 KiB
Diff

From 8fe5ab411209ac6e2c7021131e622fd004506d1a Mon Sep 17 00:00:00 2001
From: Simon Gaiser <simon@invisiblethingslab.com>
Date: Thu, 15 Mar 2018 03:43:22 +0100
Subject: [PATCH 3/3] xen: xenbus_dev_frontend: Verify body of
XS_TRANSACTION_END
By guaranteeing that the argument of XS_TRANSACTION_END is valid we can
assume that the transaction has been closed when we get an XS_ERROR
response from xenstore (Note that we already verify that it's a valid
transaction id).
Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
drivers/xen/xenbus/xenbus_dev_frontend.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 81a84b3c1c50..0d6d9264d6a9 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -429,6 +429,10 @@ static int xenbus_write_transaction(unsigned msg_type,
{
int rc;
struct xenbus_transaction_holder *trans = NULL;
+ struct {
+ struct xsd_sockmsg hdr;
+ char body[];
+ } *msg = (void *)u->u.buffer;
if (msg_type == XS_TRANSACTION_START) {
trans = kzalloc(sizeof(*trans), GFP_KERNEL);
@@ -437,11 +441,15 @@ static int xenbus_write_transaction(unsigned msg_type,
goto out;
}
list_add(&trans->list, &u->transactions);
- } else if (u->u.msg.tx_id != 0 &&
- !xenbus_get_transaction(u, u->u.msg.tx_id))
+ } else if (msg->hdr.tx_id != 0 &&
+ !xenbus_get_transaction(u, msg->hdr.tx_id))
return xenbus_command_reply(u, XS_ERROR, "ENOENT");
+ else if (msg_type == XS_TRANSACTION_END &&
+ !(msg->hdr.len == 2 &&
+ (!strcmp(msg->body, "T") || !strcmp(msg->body, "F"))))
+ return xenbus_command_reply(u, XS_ERROR, "EINVAL");
- rc = xenbus_dev_request_and_reply(&u->u.msg, u);
+ rc = xenbus_dev_request_and_reply(&msg->hdr, u);
if (rc && trans) {
list_del(&trans->list);
kfree(trans);
--
2.16.2