* [PATCH] hw/pvrdma: Protect against buggy or malicious guest driver
@ 2022-03-21 13:11 Yuval Shaia
2022-03-22 12:27 ` Marcel Apfelbaum
0 siblings, 1 reply; 3+ messages in thread
From: Yuval Shaia @ 2022-03-21 13:11 UTC (permalink / raw)
To: qemu-devel, yuval.shaia.ml, marcel.apfelbaum, mcascell, wxhusst
Guest driver might execute HW commands when shared buffers are not yet
allocated.
This might happen on purpose (malicious guest) or because some other
guest/host address mapping.
We need to protect againts such case.
Reported-by: Mauro Matteo Cascella <mcascell@redhat.com>
Signed-off-by: Yuval Shaia <yuval.shaia.ml@gmail.com>
---
hw/rdma/vmw/pvrdma_cmd.c | 6 ++++++
hw/rdma/vmw/pvrdma_main.c | 9 +++++----
2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/hw/rdma/vmw/pvrdma_cmd.c b/hw/rdma/vmw/pvrdma_cmd.c
index da7ddfa548..89db963c46 100644
--- a/hw/rdma/vmw/pvrdma_cmd.c
+++ b/hw/rdma/vmw/pvrdma_cmd.c
@@ -796,6 +796,12 @@ int pvrdma_exec_cmd(PVRDMADev *dev)
dsr_info = &dev->dsr_info;
+ if (!dsr_info->dsr) {
+ /* Buggy or malicious guest driver */
+ rdma_error_report("Exec command without dsr, req or rsp buffers");
+ goto out;
+ }
+
if (dsr_info->req->hdr.cmd >= sizeof(cmd_handlers) /
sizeof(struct cmd_handler)) {
rdma_error_report("Unsupported command");
diff --git a/hw/rdma/vmw/pvrdma_main.c b/hw/rdma/vmw/pvrdma_main.c
index 91206dbb8e..aae382af59 100644
--- a/hw/rdma/vmw/pvrdma_main.c
+++ b/hw/rdma/vmw/pvrdma_main.c
@@ -159,13 +159,13 @@ static void free_dsr(PVRDMADev *dev)
free_dev_ring(pci_dev, &dev->dsr_info.cq, dev->dsr_info.cq_ring_state);
rdma_pci_dma_unmap(pci_dev, dev->dsr_info.req,
- sizeof(union pvrdma_cmd_req));
+ sizeof(union pvrdma_cmd_req));
rdma_pci_dma_unmap(pci_dev, dev->dsr_info.rsp,
- sizeof(union pvrdma_cmd_resp));
+ sizeof(union pvrdma_cmd_resp));
rdma_pci_dma_unmap(pci_dev, dev->dsr_info.dsr,
- sizeof(struct pvrdma_device_shared_region));
+ sizeof(struct pvrdma_device_shared_region));
dev->dsr_info.dsr = NULL;
}
@@ -249,7 +249,8 @@ static void init_dsr_dev_caps(PVRDMADev *dev)
{
struct pvrdma_device_shared_region *dsr;
- if (dev->dsr_info.dsr == NULL) {
+ if (!dev->dsr_info.dsr) {
+ /* Buggy or malicious guest driver */
rdma_error_report("Can't initialized DSR");
return;
}
--
2.20.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] hw/pvrdma: Protect against buggy or malicious guest driver
2022-03-21 13:11 [PATCH] hw/pvrdma: Protect against buggy or malicious guest driver Yuval Shaia
@ 2022-03-22 12:27 ` Marcel Apfelbaum
2022-03-29 10:10 ` [PATCH-for-7.0] " Philippe Mathieu-Daudé
0 siblings, 1 reply; 3+ messages in thread
From: Marcel Apfelbaum @ 2022-03-22 12:27 UTC (permalink / raw)
To: Yuval Shaia; +Cc: wxhusst, Mauro Matteo Cascella, qemu devel list
Hi Yuval
On Mon, Mar 21, 2022 at 2:11 PM Yuval Shaia <yuval.shaia.ml@gmail.com> wrote:
>
> Guest driver might execute HW commands when shared buffers are not yet
> allocated.
> This might happen on purpose (malicious guest) or because some other
> guest/host address mapping.
> We need to protect againts such case.
>
> Reported-by: Mauro Matteo Cascella <mcascell@redhat.com>
> Signed-off-by: Yuval Shaia <yuval.shaia.ml@gmail.com>
> ---
> hw/rdma/vmw/pvrdma_cmd.c | 6 ++++++
> hw/rdma/vmw/pvrdma_main.c | 9 +++++----
> 2 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/hw/rdma/vmw/pvrdma_cmd.c b/hw/rdma/vmw/pvrdma_cmd.c
> index da7ddfa548..89db963c46 100644
> --- a/hw/rdma/vmw/pvrdma_cmd.c
> +++ b/hw/rdma/vmw/pvrdma_cmd.c
> @@ -796,6 +796,12 @@ int pvrdma_exec_cmd(PVRDMADev *dev)
>
> dsr_info = &dev->dsr_info;
>
> + if (!dsr_info->dsr) {
> + /* Buggy or malicious guest driver */
> + rdma_error_report("Exec command without dsr, req or rsp buffers");
> + goto out;
> + }
> +
> if (dsr_info->req->hdr.cmd >= sizeof(cmd_handlers) /
> sizeof(struct cmd_handler)) {
> rdma_error_report("Unsupported command");
> diff --git a/hw/rdma/vmw/pvrdma_main.c b/hw/rdma/vmw/pvrdma_main.c
> index 91206dbb8e..aae382af59 100644
> --- a/hw/rdma/vmw/pvrdma_main.c
> +++ b/hw/rdma/vmw/pvrdma_main.c
> @@ -159,13 +159,13 @@ static void free_dsr(PVRDMADev *dev)
> free_dev_ring(pci_dev, &dev->dsr_info.cq, dev->dsr_info.cq_ring_state);
>
> rdma_pci_dma_unmap(pci_dev, dev->dsr_info.req,
> - sizeof(union pvrdma_cmd_req));
> + sizeof(union pvrdma_cmd_req));
>
> rdma_pci_dma_unmap(pci_dev, dev->dsr_info.rsp,
> - sizeof(union pvrdma_cmd_resp));
> + sizeof(union pvrdma_cmd_resp));
>
> rdma_pci_dma_unmap(pci_dev, dev->dsr_info.dsr,
> - sizeof(struct pvrdma_device_shared_region));
> + sizeof(struct pvrdma_device_shared_region));
>
Nit: the above changes are not related to the patch, maybe drop them?
Reviewed-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Thanks,
Marcel
> dev->dsr_info.dsr = NULL;
> }
> @@ -249,7 +249,8 @@ static void init_dsr_dev_caps(PVRDMADev *dev)
> {
> struct pvrdma_device_shared_region *dsr;
>
> - if (dev->dsr_info.dsr == NULL) {
> + if (!dev->dsr_info.dsr) {
> + /* Buggy or malicious guest driver */
> rdma_error_report("Can't initialized DSR");
> return;
> }
> --
> 2.20.1
>
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH-for-7.0] hw/pvrdma: Protect against buggy or malicious guest driver
2022-03-22 12:27 ` Marcel Apfelbaum
@ 2022-03-29 10:10 ` Philippe Mathieu-Daudé
0 siblings, 0 replies; 3+ messages in thread
From: Philippe Mathieu-Daudé @ 2022-03-29 10:10 UTC (permalink / raw)
To: Marcel Apfelbaum, Yuval Shaia
Cc: wxhusst, Peter Maydell, Mauro Matteo Cascella, qemu devel list
On 22/3/22 13:27, Marcel Apfelbaum wrote:
> Hi Yuval
>
> On Mon, Mar 21, 2022 at 2:11 PM Yuval Shaia <yuval.shaia.ml@gmail.com> wrote:
>>
>> Guest driver might execute HW commands when shared buffers are not yet
>> allocated.
>> This might happen on purpose (malicious guest) or because some other
>> guest/host address mapping.
>> We need to protect againts such case.
>>
Fixes: CVE-2022-1050
>> Reported-by: Mauro Matteo Cascella <mcascell@redhat.com>
>> Signed-off-by: Yuval Shaia <yuval.shaia.ml@gmail.com>
>> ---
>> hw/rdma/vmw/pvrdma_cmd.c | 6 ++++++
>> hw/rdma/vmw/pvrdma_main.c | 9 +++++----
>> 2 files changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/hw/rdma/vmw/pvrdma_cmd.c b/hw/rdma/vmw/pvrdma_cmd.c
>> index da7ddfa548..89db963c46 100644
>> --- a/hw/rdma/vmw/pvrdma_cmd.c
>> +++ b/hw/rdma/vmw/pvrdma_cmd.c
>> @@ -796,6 +796,12 @@ int pvrdma_exec_cmd(PVRDMADev *dev)
>>
>> dsr_info = &dev->dsr_info;
>>
>> + if (!dsr_info->dsr) {
>> + /* Buggy or malicious guest driver */
>> + rdma_error_report("Exec command without dsr, req or rsp buffers");
>> + goto out;
>> + }
>> +
>> if (dsr_info->req->hdr.cmd >= sizeof(cmd_handlers) /
>> sizeof(struct cmd_handler)) {
>> rdma_error_report("Unsupported command");
>> diff --git a/hw/rdma/vmw/pvrdma_main.c b/hw/rdma/vmw/pvrdma_main.c
>> index 91206dbb8e..aae382af59 100644
>> --- a/hw/rdma/vmw/pvrdma_main.c
>> +++ b/hw/rdma/vmw/pvrdma_main.c
>> @@ -159,13 +159,13 @@ static void free_dsr(PVRDMADev *dev)
>> free_dev_ring(pci_dev, &dev->dsr_info.cq, dev->dsr_info.cq_ring_state);
>>
>> rdma_pci_dma_unmap(pci_dev, dev->dsr_info.req,
>> - sizeof(union pvrdma_cmd_req));
>> + sizeof(union pvrdma_cmd_req));
>>
>> rdma_pci_dma_unmap(pci_dev, dev->dsr_info.rsp,
>> - sizeof(union pvrdma_cmd_resp));
>> + sizeof(union pvrdma_cmd_resp));
>>
>> rdma_pci_dma_unmap(pci_dev, dev->dsr_info.dsr,
>> - sizeof(struct pvrdma_device_shared_region));
>> + sizeof(struct pvrdma_device_shared_region));
>>
>
> Nit: the above changes are not related to the patch, maybe drop them?
Yes please.
>
> Reviewed-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
>
> Thanks,
> Marcel
>
>> dev->dsr_info.dsr = NULL;
>> }
>> @@ -249,7 +249,8 @@ static void init_dsr_dev_caps(PVRDMADev *dev)
>> {
>> struct pvrdma_device_shared_region *dsr;
>>
>> - if (dev->dsr_info.dsr == NULL) {
>> + if (!dev->dsr_info.dsr) {
>> + /* Buggy or malicious guest driver */
>> rdma_error_report("Can't initialized DSR");
>> return;
>> }
>> --
>> 2.20.1
>>
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-03-29 10:13 UTC | newest]
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2022-03-21 13:11 [PATCH] hw/pvrdma: Protect against buggy or malicious guest driver Yuval Shaia
2022-03-22 12:27 ` Marcel Apfelbaum
2022-03-29 10:10 ` [PATCH-for-7.0] " Philippe Mathieu-Daudé
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