From: Eric Auger Date: Mon, 21 Nov 2016 06:21:02 +0000 (+0100) Subject: vfio: fix vfio_info_cap_add/shift X-Git-Tag: v4.10-rc1~156^2~7 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=5ba6de98c78ac45166036516e34bec487887ba5d;p=linux.git 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 Reviewed-by: David Hildenbrand Signed-off-by: Alex Williamson --- diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index c8150674787c..0aac3ca54a53 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -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);