c4c303c7c5
During repeated kexec boots xenwatch_thread() can crash because xenbus_watch->callback is cleared by xenbus_watch_path() if a node/token combo for a new watch happens to match an already registered watch from an old kernel. In this case xs_watch returns -EEXISTS, then register_xenbus_watch() does not remove the to-be-registered watch from the list of active watches but returns the -EEXISTS to the caller anyway. Because the watch is still active in xenstored it will cause an event which will arrive in the new kernel. process_msg() will find the encapsulated struct xenbus_watch in its list of registered watches and puts the "empty" watch handle in the queue for xenwatch_thread(). xenwatch_thread() then calls ->callback which was cleared earlier by xenbus_watch_path(). To prevent that crash in a guest running on an old xen toolstack remove the special -EEXIST handling. v2: - remove the EEXIST handing in register_xenbus_watch() instead of checking for ->callback in process_msg() Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Olaf Hering <olaf@aepfle.de> |
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| .. | ||
| xenbus | ||
| xenfs | ||
| balloon.c | ||
| biomerge.c | ||
| cpu_hotplug.c | ||
| events.c | ||
| evtchn.c | ||
| features.c | ||
| gntalloc.c | ||
| gntdev.c | ||
| grant-table.c | ||
| Kconfig | ||
| Makefile | ||
| manage.c | ||
| pci.c | ||
| platform-pci.c | ||
| swiotlb-xen.c | ||
| sys-hypervisor.c | ||
| tmem.c | ||
| xen-balloon.c | ||
| xencomm.c | ||