From 1c33522995c91a07d6c06f04160af7aaa5d89315 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Wed, 11 Mar 2015 13:51:17 +0000 Subject: xen-pciback: limit guest control of command register commit af6fc858a35b90e89ea7a7ee58e66628c55c776b upstream. Otherwise the guest can abuse that control to cause e.g. PCIe Unsupported Request responses by disabling memory and/or I/O decoding and subsequently causing (CPU side) accesses to the respective address ranges, which (depending on system configuration) may be fatal to the host. Note that to alter any of the bits collected together as PCI_COMMAND_GUEST permissive mode is now required to be enabled globally or on the specific device. This is CVE-2015-2150 / XSA-120. Signed-off-by: Jan Beulich Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: David Vrabel Signed-off-by: Greg Kroah-Hartman --- drivers/xen/xen-pciback/conf_space.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/xen/xen-pciback/conf_space.h') diff --git a/drivers/xen/xen-pciback/conf_space.h b/drivers/xen/xen-pciback/conf_space.h index e56c934ad137..2e1d73d1d5d0 100644 --- a/drivers/xen/xen-pciback/conf_space.h +++ b/drivers/xen/xen-pciback/conf_space.h @@ -64,6 +64,8 @@ struct config_field_entry { void *data; }; +extern bool permissive; + #define OFFSET(cfg_entry) ((cfg_entry)->base_offset+(cfg_entry)->field->offset) /* Add fields to a device - the add_fields macro expects to get a pointer to -- cgit v1.2.3