From: Jennifer Herbert Date: Thu, 5 Feb 2015 14:45:40 +0000 (+0000) Subject: xenbus: Add proper handling of XS_ERROR from Xenbus for transactions. X-Git-Tag: firefly_0821_release~176^2~2383^2~1 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a2e75bc2ee207351e6806e77a5379c6c1dd4598a;p=firefly-linux-kernel-4.4.55.git xenbus: Add proper handling of XS_ERROR from Xenbus for transactions. If Xenstore sends back a XS_ERROR for TRANSACTION_END, the driver BUGs because it cannot find the matching transaction in the list. For TRANSACTION_START, it leaks memory. Check the message as returned from xenbus_dev_request_and_reply(), and clean up for TRANSACTION_START or discard the error for TRANSACTION_END. Signed-off-by: Jennifer Herbert Signed-off-by: David Vrabel --- diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c index 85534ea63555..9433e46518c8 100644 --- a/drivers/xen/xenbus/xenbus_dev_frontend.c +++ b/drivers/xen/xenbus/xenbus_dev_frontend.c @@ -326,10 +326,13 @@ static int xenbus_write_transaction(unsigned msg_type, } if (msg_type == XS_TRANSACTION_START) { - trans->handle.id = simple_strtoul(reply, NULL, 0); - - list_add(&trans->list, &u->transactions); - } else if (msg_type == XS_TRANSACTION_END) { + if (u->u.msg.type == XS_ERROR) + kfree(trans); + else { + trans->handle.id = simple_strtoul(reply, NULL, 0); + 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;