If the log base mmap_offset is larger than mmap_size then it points
outside the mmap region. We must not write to memory outside the mmap
region, so validate mmap_offset in vhost_user_set_log_base().
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
lib/librte_vhost/vhost_user.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 48b493d70..fd47404ce 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -1005,6 +1005,15 @@ vhost_user_set_log_base(struct virtio_net *dev, struct
VhostUserMsg *msg)
size = msg->payload.log.mmap_size;
off = msg->payload.log.mmap_offset;
+
+ /* Don't allow mmap_offset to point outside the mmap region */
+ if (off > size) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "log offset %#"PRIx64" exceeds log size %#"PRIx64"\n",
+ off, size);
+ return -1;
+ }
+
RTE_LOG(INFO, VHOST_CONFIG,
"log mmap size: %"PRId64", offset: %"PRId64"\n",
size, off);
--
2.14.3
