kevin/linux
1
Fork 0
Code

virtio_pci: Fix admin vq cleanup by using correct info pointer

Browse Source 
vp_modern_avq_cleanup() and vp_del_vqs() clean up admin vq
resources by virtio_pci_vq_info pointer. The info pointer of admin
vq is stored in vp_dev->admin_vq.info instead of vp_dev->vqs[].
Using the info pointer from vp_dev->vqs[] for admin vq causes a
kernel NULL pointer dereference bug.
In vp_modern_avq_cleanup() and vp_del_vqs(), get the info pointer
from vp_dev->admin_vq.info for admin vq to clean up the resources.
Also make info ptr as argument of vp_del_vq() to be symmetric with
vp_setup_vq().

vp_reset calls vp_modern_avq_cleanup, and causes the Call Trace:
==================================================================
BUG: kernel NULL pointer dereference, address:0000000000000000
...
CPU: 49 UID: 0 PID: 4439 Comm: modprobe Not tainted 6.11.0-rc5 #1
RIP: 0010:vp_reset+0x57/0x90 [virtio_pci]
Call Trace:
 <TASK>
...
 ? vp_reset+0x57/0x90 [virtio_pci]
 ? vp_reset+0x38/0x90 [virtio_pci]
 virtio_reset_device+0x1d/0x30
 remove_vq_common+0x1c/0x1a0 [virtio_net]
 virtnet_remove+0xa1/0xc0 [virtio_net]
 virtio_dev_remove+0x46/0xa0
...
 virtio_pci_driver_exit+0x14/0x810 [virtio_pci]
==================================================================

Fixes: 4c3b54af90 ("virtio_pci_modern: use completion instead of busy loop to wait on admin cmd result")
Signed-off-by: Feng Liu <feliu@nvidia.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Message-Id: <20241024135406.81388-1-feliu@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Feng Liu 2024-10-24 09:54:06 -04:00 committed by Michael S. Tsirkin
parent 7f8825b2a7
commit 97ee04feb6
3 changed files with 20 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
drivers/virtio/virtio_pci_common.c
View File

@ -24,6 +24,16 @@ MODULE_PARM_DESC(force_legacy,
"Force legacy mode for transitional virtio 1 devices");
#endif
bool vp_is_avq(struct virtio_device *vdev, unsigned int index)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
return false;
return index == vp_dev->admin_vq.vq_index;
}
/* wait for pending irq handlers */
void vp_synchronize_vectors(struct virtio_device *vdev)
{
@ -234,10 +244,9 @@ out_info:
return vq;
}
static void vp_del_vq(struct virtqueue *vq)
static void vp_del_vq(struct virtqueue *vq, struct virtio_pci_vq_info *info)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
unsigned long flags;
/*
@ -258,13 +267,16 @@ static void vp_del_vq(struct virtqueue *vq)
void vp_del_vqs(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
struct virtio_pci_vq_info *info;
struct virtqueue *vq, *n;
int i;
list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
if (vp_dev->per_vq_vectors) {
int v = vp_dev->vqs[vq->index]->msix_vector;
info = vp_is_avq(vdev, vq->index) ? vp_dev->admin_vq.info :
vp_dev->vqs[vq->index];
if (vp_dev->per_vq_vectors) {
int v = info->msix_vector;
if (v != VIRTIO_MSI_NO_VECTOR &&
!vp_is_slow_path_vector(v)) {
int irq = pci_irq_vector(vp_dev->pci_dev, v);
@ -273,7 +285,7 @@ void vp_del_vqs(struct virtio_device *vdev)
free_irq(irq, vq);
}
}
vp_del_vq(vq);
vp_del_vq(vq, info);
}
vp_dev->per_vq_vectors = false;
@ -354,7 +366,7 @@ vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx,
vring_interrupt, 0,
vp_dev->msix_names[msix_vec], vq);
if (err) {
vp_del_vq(vq);
vp_del_vq(vq, *p_info);
return ERR_PTR(err);
}

1
drivers/virtio/virtio_pci_common.h
View File

@ -178,6 +178,7 @@ struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev);
#define VIRTIO_ADMIN_CMD_BITMAP 0
#endif
bool vp_is_avq(struct virtio_device *vdev, unsigned int index);
void vp_modern_avq_done(struct virtqueue *vq);
int vp_modern_admin_cmd_exec(struct virtio_device *vdev,
struct virtio_admin_cmd *cmd);

12
drivers/virtio/virtio_pci_modern.c
View File

@ -43,16 +43,6 @@ static int vp_avq_index(struct virtio_device *vdev, u16 *index, u16 *num)
return 0;
}
static bool vp_is_avq(struct virtio_device *vdev, unsigned int index)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
return false;
return index == vp_dev->admin_vq.vq_index;
}
void vp_modern_avq_done(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
@ -245,7 +235,7 @@ static void vp_modern_avq_cleanup(struct virtio_device *vdev)
if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
return;
vq = vp_dev->vqs[vp_dev->admin_vq.vq_index]->vq;
vq = vp_dev->admin_vq.info->vq;
if (!vq)
return;