[PATCH 5.11 05/12] xen/arm: dont ignore return errors from set_phys_to_machine

Greg Kroah-Hartman
2021-02-22T12:18:06Z

From: Stefano Stabellini <stefano.stabellini@xilinx.com>

commit 36bf1dfb8b266e089afa9b7b984217f17027bf35 upstream.

set_phys_to_machine can fail due to lack of memory, see the kzalloc call
in arch/arm/xen/p2m.c:__set_phys_to_machine_multi.

Don't ignore the potential return error in set_foreign_p2m_mapping,
returning it to the caller instead.

This is part of XSA-361.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Cc: stable@vger.kernel.org
Reviewed-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/arm/xen/p2m.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/arm/xen/p2m.c
+++ b/arch/arm/xen/p2m.c
@@ -95,8 +95,10 @@ int set_foreign_p2m_mapping(struct gntta
for (i = 0; i < count; i++) {
if (map_ops[i].status)
continue;
- set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
- map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT);
+ if (unlikely(!set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
+ map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT))) {
+ return -ENOMEM;
+ }
}

return 0;