From cef25866f41c45a01a933adb032b0dcfb25b847a Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Mon, 26 Jun 2023 18:23:03 -0500 Subject: [PATCH] vhost: add helper to parse userspace vring state/file The next patches add new vhost worker ioctls which will need to get a vhost_virtqueue from a userspace struct which specifies the vq's index. This moves the vhost_vring_ioctl code to do this to a helper so it can be shared. Signed-off-by: Mike Christie Message-Id: <20230626232307.97930-14-michael.christie@oracle.com> Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 29 ++++++++++++++++++++++------- 1 file changed, 22 insertions(+), 7 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 6cadbc6e6d11..12203d3893c5 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -599,6 +599,27 @@ free_worker: return NULL; } +static int vhost_get_vq_from_user(struct vhost_dev *dev, void __user *argp, + struct vhost_virtqueue **vq, u32 *id) +{ + u32 __user *idxp = argp; + u32 idx; + long r; + + r = get_user(idx, idxp); + if (r < 0) + return r; + + if (idx >= dev->nvqs) + return -ENOBUFS; + + idx = array_index_nospec(idx, dev->nvqs); + + *vq = dev->vqs[idx]; + *id = idx; + return 0; +} + /* Caller should have device mutex */ long vhost_dev_set_owner(struct vhost_dev *dev) { @@ -1618,21 +1639,15 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg struct file *eventfp, *filep = NULL; bool pollstart = false, pollstop = false; struct eventfd_ctx *ctx = NULL; - u32 __user *idxp = argp; struct vhost_virtqueue *vq; struct vhost_vring_state s; struct vhost_vring_file f; u32 idx; long r; - r = get_user(idx, idxp); + r = vhost_get_vq_from_user(d, argp, &vq, &idx); if (r < 0) return r; - if (idx >= d->nvqs) - return -ENOBUFS; - - idx = array_index_nospec(idx, d->nvqs); - vq = d->vqs[idx]; if (ioctl == VHOST_SET_VRING_NUM || ioctl == VHOST_SET_VRING_ADDR) { -- 2.11.0