2019-09-06 05:13:04

by Vivek Goyal

[permalink] [raw]

Subject: [PATCH 13/18] virtiofs: Do not access virtqueue in request submission path

---

In request submission path it is possible that virtqueue is already gone
due to driver->remove(). So do not access it in dev_dbg(). Use pr_debug()
instead.

If virtuqueue is gone, this will result in NULL pointer deference.

Signed-off-by: Vivek Goyal <[email protected]>
---
fs/fuse/virtio_fs.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 40259368a6bd..01bbf2c0e144 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -888,10 +888,10 @@ __releases(fiq->waitq.lock)
fs = fiq->priv;
fc = fs->vqs[queue_id].fud->fc;

- dev_dbg(&fs->vqs[queue_id].vq->vdev->dev,
- "%s: opcode %u unique %#llx nodeid %#llx in.len %u out.len %u\n",
- __func__, req->in.h.opcode, req->in.h.unique, req->in.h.nodeid,
- req->in.h.len, fuse_len_args(req->out.numargs, req->out.args));
+ pr_debug("%s: opcode %u unique %#llx nodeid %#llx in.len %u out.len %u"
+ "\n", __func__, req->in.h.opcode, req->in.h.unique,
+ req->in.h.nodeid, req->in.h.len,
+ fuse_len_args(req->out.numargs, req->out.args));

fpq = &fs->vqs[queue_id].fud->pq;
spin_lock(&fpq->lock);
--
2.20.1

2019-09-06 15:12:51

by Stefan Hajnoczi

[permalink] [raw]

Subject: Re: [PATCH 13/18] virtiofs: Do not access virtqueue in request submission path

---

On Thu, Sep 05, 2019 at 03:48:54PM -0400, Vivek Goyal wrote:
> In request submission path it is possible that virtqueue is already gone
> due to driver->remove(). So do not access it in dev_dbg(). Use pr_debug()
> instead.
>
> If virtuqueue is gone, this will result in NULL pointer deference.
>
> Signed-off-by: Vivek Goyal <[email protected]>
> ---
> fs/fuse/virtio_fs.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)

Reviewed-by: Stefan Hajnoczi <[email protected]>

---

Attachments:

(No filename) (505.00 B)
signature.asc (499.00 B)
Download all attachments