aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJan Beulich <JBeulich@suse.com>2016-07-07 01:23:57 -0600
committerDavid Vrabel <david.vrabel@citrix.com>2016-07-07 12:19:52 +0100
commit0beef634b86a1350c31da5fcc2992f0d7c8a622b (patch)
tree89be6a7c5e2d6af18fbc9935f3afaae9c42f0970
parentd2bd05d88d245c13b64c3bf9c8927a1c56453d8c (diff)
downloadlinux-stericsson-0beef634b86a1350c31da5fcc2992f0d7c8a622b.tar.gz
xenbus: don't BUG() on user mode induced condition
Inability to locate a user mode specified transaction ID should not lead to a kernel crash. For other than XS_TRANSACTION_START also don't issue anything to xenbus if the specified ID doesn't match that of any active transaction. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
-rw-r--r--drivers/xen/xenbus/xenbus_dev_frontend.c14
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index cacf30d14747..7487971f9f78 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -316,11 +316,18 @@ static int xenbus_write_transaction(unsigned msg_type,
rc = -ENOMEM;
goto out;
}
+ } else {
+ list_for_each_entry(trans, &u->transactions, list)
+ if (trans->handle.id == u->u.msg.tx_id)
+ break;
+ if (&trans->list == &u->transactions)
+ return -ESRCH;
}
reply = xenbus_dev_request_and_reply(&u->u.msg);
if (IS_ERR(reply)) {
- kfree(trans);
+ if (msg_type == XS_TRANSACTION_START)
+ kfree(trans);
rc = PTR_ERR(reply);
goto out;
}
@@ -333,12 +340,7 @@ static int xenbus_write_transaction(unsigned msg_type,
list_add(&trans->list, &u->transactions);
}
} else if (u->u.msg.type == XS_TRANSACTION_END) {
- list_for_each_entry(trans, &u->transactions, list)
- if (trans->handle.id == u->u.msg.tx_id)
- break;
- BUG_ON(&trans->list == &u->transactions);
list_del(&trans->list);
-
kfree(trans);
}