Dongli Zhang 4a8c31a1c6 xen/blkback: rework connect_ring() to avoid inconsistent xenstore 'ring-page-order' set by malicious blkfront ... The xenstore 'ring-page-order' is used globally for each blkback queue and therefore should be read from xenstore only once. However, it is obtained in read_per_ring_refs() which might be called multiple times during the initialization of each blkback queue. If the blkfront is malicious and the 'ring-page-order' is set in different value by blkfront every time before blkback reads it, this may end up at the "WARN_ON(i != (XEN_BLKIF_REQS_PER_PAGE * blkif->nr_ring_pages));" in xen_blkif_disconnect() when frontend is destroyed. This patch reworks connect_ring() to read xenstore 'ring-page-order' only once. Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>		2019-02-24 10:17:56 -05:00
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Makefile	xen/blkback: Squash vbd.c,interface.c in blkback.c and xenbus.c respectivly.	2011-04-20 11:57:59 -04:00
blkback.c	xen/blkback: move persistent grants flags to bool	2018-08-27 12:12:04 -04:00
common.h	xen/blkback: remove unused pers_gnts_lock from struct xen_blkif_ring	2018-08-27 12:12:04 -04:00
xenbus.c	xen/blkback: rework connect_ring() to avoid inconsistent xenstore 'ring-page-order' set by malicious blkfront	2019-02-24 10:17:56 -05:00