From 0fe99cf73eec0426ef9cb5eb71c1b8b4de40162c Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 5 Feb 2018 13:16:00 +0100 Subject: [PATCH] vhost: check overflow before mmap If memory_size + mmap_offset overflows then the memory region is bogus. Do not use the overflowed mmap_size value for mmap(). Signed-off-by: Stefan Hajnoczi Reviewed-by: Maxime Coquelin --- lib/librte_vhost/vhost_user.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index 7a8670c8d1..8ec51c9f88 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -730,7 +730,17 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg) reg->fd = fd; mmap_offset = memory.regions[i].mmap_offset; - mmap_size = reg->size + mmap_offset; + + /* Check for memory_size + mmap_offset overflow */ + if (mmap_offset >= -reg->size) { + RTE_LOG(ERR, VHOST_CONFIG, + "mmap_offset (%#"PRIx64") and memory_size " + "(%#"PRIx64") overflow\n", + mmap_offset, reg->size); + goto err_mmap; + } + + mmap_size = reg->size + mmap_offset; /* mmap() without flag of MAP_ANONYMOUS, should be called * with length argument aligned with hugepagesz at older -- 2.20.1