When an MSI descriptor was not available, the error path would try to
unbind an irq that was never acquired - potentially unbinding an
unrelated irq.

Fixes: 4892c9b4ada9f9 ("xen: add support for MSI message groups")
Reported-by: Hooman Mirhadi <mirha...@amazon.com>
CC: <sta...@vger.kernel.org>
CC: Roger Pau Monné <roger....@citrix.com>
CC: Boris Ostrovsky <boris.ostrov...@oracle.com>
CC: Eduardo Valentin <edu...@amazon.com>
CC: Juergen Gross <jgr...@suse.com>
CC: Thomas Gleixner <t...@linutronix.de>
CC: "K. Y. Srinivasan" <k...@microsoft.com>
CC: Liu Shuo <shuo.a....@intel.com>
CC: Anoob Soman <anoob.so...@citrix.com>
Signed-off-by: Amit Shah <a...@amazon.com>
---
 drivers/xen/events/events_base.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 1ab4bd1..c86d10e 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -755,8 +755,10 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct 
msi_desc *msidesc,
        mutex_unlock(&irq_mapping_update_lock);
        return irq;
 error_irq:
-       for (; i >= 0; i--)
+       while (i > 0) {
+               i--;
                __unbind_from_irq(irq + i);
+       }
        mutex_unlock(&irq_mapping_update_lock);
        return ret;
 }
-- 
2.7.3.AMZN

Amazon Development Center Germany GmbH
Berlin - Dresden - Aachen
main office: Krausenstr. 38, 10117 Berlin
Geschaeftsfuehrer: Dr. Ralf Herbrich, Christian Schlaeger
Ust-ID: DE289237879
Eingetragen am Amtsgericht Charlottenburg HRB 149173 B
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

Reply via email to