Commit b93008d1 authored Mar 15, 2018 by Simon Gaiser Committed by Boris Ostrovsky Mar 21, 2018

xen: xenbus: Catch closing of non existent transactions



Users of the xenbus functions should never close a non existent
transaction (for example by trying to closing the same transaction
twice) but better catch it in xs_request_exit() than to corrupt the
reference counter.

Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

parent 2a22ee6c

drivers/xen/xenbus/xenbus_xs.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -140,7 +140,9 @@ void xs_request_exit(struct xb_req_data *req)
		spin_lock(&xs_state_lock);
		xs_state_users--;
		if ((req->type == XS_TRANSACTION_START && req->msg.type == XS_ERROR) \|\|
		req->type == XS_TRANSACTION_END)
		(req->type == XS_TRANSACTION_END &&
		!WARN_ON_ONCE(req->msg.type == XS_ERROR &&
		!strcmp(req->body, "ENOENT"))))
		xs_state_users--;
		spin_unlock(&xs_state_lock);

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