From 813dbeb656d6c90266f251d8bd2b02d445afa63f Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Tue, 9 Apr 2019 12:10:25 +0800 Subject: [PATCH] vhost: reject zero size iova range We used to accept zero size iova range which will lead a infinite loop in translate_desc(). Fixing this by failing the request in this case. Reported-by: syzbot+d21e6e297322a900c128@syzkaller.appspotmail.com Fixes: 6b1e6cc7 ("vhost: new device IOTLB API") Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller --- drivers/vhost/vhost.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 5ace833de74620..351af88231ada1 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -911,8 +911,12 @@ static int vhost_new_umem_range(struct vhost_umem *umem, u64 start, u64 size, u64 end, u64 userspace_addr, int perm) { - struct vhost_umem_node *tmp, *node = kmalloc(sizeof(*node), GFP_ATOMIC); + struct vhost_umem_node *tmp, *node; + if (!size) + return -EFAULT; + + node = kmalloc(sizeof(*node), GFP_ATOMIC); if (!node) return -ENOMEM;