vfio: fix vfio_info_cap_add/shift

Capability header next field is an offset relative to the start of
the INFO buffer. tmp->next is assigned the proper value but iterations
implemented in vfio_info_cap_add and vfio_info_cap_shift use next
as an offset between the headers. When coping with multiple capabilities
this leads to an Oops.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Eric Auger 2016-11-21 07:21:02 +01:00 committed by Alex Williamson
parent f4cb410019
commit 5ba6de98c7

View File

@ -1780,7 +1780,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
header->version = version;
/* Add to the end of the capability chain */
for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next)
for (tmp = buf; tmp->next; tmp = buf + tmp->next)
; /* nothing */
tmp->next = caps->size;
@ -1793,8 +1793,9 @@ EXPORT_SYMBOL_GPL(vfio_info_cap_add);
void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
{
struct vfio_info_cap_header *tmp;
void *buf = (void *)caps->buf;
for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset)
for (tmp = buf; tmp->next; tmp = buf + tmp->next - offset)
tmp->next += offset;
}
EXPORT_SYMBOL(vfio_info_cap_shift);