4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 74ad7419489ddade8044e3c9ab064ad656520306 ]
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 ptikhomirov@virtuozzo.com Signed-off-by: Michael S. Tsirkin mst@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 5eaeca805c95c..b214a72d5caad 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1035,8 +1035,10 @@ 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: @@ -1055,8 +1057,10 @@ 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;