From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 4.19 61/83] vhost: return EINVAL if iovecs size does not match the message size Date: Tue, 12 Feb 2019 21:36:39 -0500 Message-ID: <20190213023701.20286-61-sashal@kernel.org> References: <20190213023701.20286-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: Pavel Tikhomirov , "Michael S . Tsirkin" , Sasha Levin , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Return-path: In-Reply-To: <20190213023701.20286-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org From: Pavel Tikhomirov [ 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 Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin --- 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 cf82e7266397..7a07b0e86644 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; -- 2.19.1