bus/vmbus: calcuate the correct start address for mapping ring buffer
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Commit Message
From: Long Li <longli@microsoft.com>
vmbus_map_addr is used as the next start virutal address for mapping ring
buffer. However it's updated based on ring_buf, which is a pointer to an
address on the stack. The next ring buffer may be mapped to an unexpected
address.
Fix this by calculating vmbus_map_addr based on returned virtual address.
Signed-off-by: Long Li <longli@microsoft.com>
---
drivers/bus/vmbus/linux/vmbus_uio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Comments
On Thu, 11 Jun 2020 17:48:25 -0700
longli@linuxonhyperv.com wrote:
> From: Long Li <longli@microsoft.com>
>
> vmbus_map_addr is used as the next start virutal address for mapping ring
> buffer. However it's updated based on ring_buf, which is a pointer to an
> address on the stack. The next ring buffer may be mapped to an unexpected
> address.
>
> Fix this by calculating vmbus_map_addr based on returned virtual address.
>
> Signed-off-by: Long Li <longli@microsoft.com>
Fixes: 3f9277031a2e ("bus/vmbus: fix check for mmap failure")
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
12/06/2020 18:06, Stephen Hemminger:
> On Thu, 11 Jun 2020 17:48:25 -0700
> longli@linuxonhyperv.com wrote:
>
> > From: Long Li <longli@microsoft.com>
> >
> > vmbus_map_addr is used as the next start virutal address for mapping ring
> > buffer. However it's updated based on ring_buf, which is a pointer to an
> > address on the stack. The next ring buffer may be mapped to an unexpected
> > address.
> >
> > Fix this by calculating vmbus_map_addr based on returned virtual address.
> >
> > Signed-off-by: Long Li <longli@microsoft.com>
>
>
> Fixes: 3f9277031a2e ("bus/vmbus: fix check for mmap failure")
> Acked-by: Stephen Hemminger <stephen@networkplumber.org>
+Cc: stable@dpdk.org
Applied, thanks
@@ -242,7 +242,7 @@ static int vmbus_uio_map_subchan(const struct rte_vmbus_device *dev,
*ring_size = file_size / 2;
*ring_buf = mapaddr;
- vmbus_map_addr = RTE_PTR_ADD(ring_buf, file_size);
+ vmbus_map_addr = RTE_PTR_ADD(mapaddr, file_size);
return 0;
}