From 74ad7419489ddade8044e3c9ab064ad656520306 Mon Sep 17 00:00:00 2001 From: Pavel Tikhomirov Date: Thu, 13 Dec 2018 17:53:50 +0300 Subject: [PATCH] vhost: return EINVAL if iovecs size does not match the message size We've failed to copy and process vhost_iotlb_msg so let userspace at least know about it. For instance before these patch the code below runs without any error: int main() { struct vhost_msg msg; struct iovec iov; int fd; fd = open("/dev/vhost-net", O_RDWR); if (fd == -1) { perror("open"); return 1; } iov.iov_base = &msg; iov.iov_len = sizeof(msg)-4; if (writev(fd, &iov,1) == -1) { perror("writev"); return 1; } return 0; } Signed-off-by: Pavel Tikhomirov Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 9f7942cbcbb2..bac939af8dbb 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1034,8 +1034,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, int type, ret; ret = copy_from_iter(&type, sizeof(type), from); - if (ret != sizeof(type)) + if (ret != sizeof(type)) { + ret = -EINVAL; goto done; + } switch (type) { case VHOST_IOTLB_MSG: @@ -1054,8 +1056,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, iov_iter_advance(from, offset); ret = copy_from_iter(&msg, sizeof(msg), from); - if (ret != sizeof(msg)) + if (ret != sizeof(msg)) { + ret = -EINVAL; goto done; + } if (vhost_process_iotlb_msg(dev, &msg)) { ret = -EFAULT; goto done; -- GitLab