We've failed to copy and process vhost_iotlb_msg so let userspace at
least know about it. For instance before these patch the code below runs
without any error:
int main()
{
struct vhost_msg msg;
struct iovec iov;
int fd;
fd = open("/dev/vhost-net", O_RDWR);
if (fd == -1) {
perror("open");
return 1;
}
iov.iov_base = &msg;
iov.iov_len = sizeof(msg)-4;
if (writev(fd, &iov,1) == -1) {
perror("writev");
return 1;
}
return 0;
}
Signed-off-by: Pavel Tikhomirov <[email protected]>
---
drivers/vhost/vhost.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 3a5f81a66d34..03014224ef13 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1024,8 +1024,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
int type, ret;
ret = copy_from_iter(&type, sizeof(type), from);
- if (ret != sizeof(type))
+ if (ret != sizeof(type)) {
+ ret = -EINVAL;
goto done;
+ }
switch (type) {
case VHOST_IOTLB_MSG:
@@ -1044,8 +1046,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
iov_iter_advance(from, offset);
ret = copy_from_iter(&msg, sizeof(msg), from);
- if (ret != sizeof(msg))
+ if (ret != sizeof(msg)) {
+ ret = -EINVAL;
goto done;
+ }
if (vhost_process_iotlb_msg(dev, &msg)) {
ret = -EFAULT;
goto done;
--
2.17.1
On Thu, Dec 13, 2018 at 05:53:50PM +0300, Pavel Tikhomirov wrote:
> We've failed to copy and process vhost_iotlb_msg so let userspace at
> least know about it. For instance before these patch the code below runs
> without any error:
>
> int main()
> {
> struct vhost_msg msg;
> struct iovec iov;
> int fd;
>
> fd = open("/dev/vhost-net", O_RDWR);
> if (fd == -1) {
> perror("open");
> return 1;
> }
>
> iov.iov_base = &msg;
> iov.iov_len = sizeof(msg)-4;
>
> if (writev(fd, &iov,1) == -1) {
> perror("writev");
> return 1;
> }
>
> return 0;
> }
>
> Signed-off-by: Pavel Tikhomirov <[email protected]>
Thanks for the patch!
> ---
> drivers/vhost/vhost.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index 3a5f81a66d34..03014224ef13 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -1024,8 +1024,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
> int type, ret;
>
> ret = copy_from_iter(&type, sizeof(type), from);
> - if (ret != sizeof(type))
> + if (ret != sizeof(type)) {
> + ret = -EINVAL;
> goto done;
> + }
>
> switch (type) {
> case VHOST_IOTLB_MSG:
should this be EFAULT rather?
> @@ -1044,8 +1046,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
>
> iov_iter_advance(from, offset);
> ret = copy_from_iter(&msg, sizeof(msg), from);
> - if (ret != sizeof(msg))
> + if (ret != sizeof(msg)) {
> + ret = -EINVAL;
> goto done;
> + }
> if (vhost_process_iotlb_msg(dev, &msg)) {
> ret = -EFAULT;
> goto done;
This too?
> --
> 2.17.1
On 12/13/2018 10:55 PM, Michael S. Tsirkin wrote:
> On Thu, Dec 13, 2018 at 05:53:50PM +0300, Pavel Tikhomirov wrote:
>> We've failed to copy and process vhost_iotlb_msg so let userspace at
>> least know about it. For instance before these patch the code below runs
>> without any error:
>>
>> int main()
>> {
>> struct vhost_msg msg;
>> struct iovec iov;
>> int fd;
>>
>> fd = open("/dev/vhost-net", O_RDWR);
>> if (fd == -1) {
>> perror("open");
>> return 1;
>> }
>>
>> iov.iov_base = &msg;
>> iov.iov_len = sizeof(msg)-4;
>>
>> if (writev(fd, &iov,1) == -1) {
>> perror("writev");
>> return 1;
>> }
>>
>> return 0;
>> }
>>
>> Signed-off-by: Pavel Tikhomirov <[email protected]>
>
> Thanks for the patch!
>
>> ---
>> drivers/vhost/vhost.c | 8 ++++++--
>> 1 file changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
>> index 3a5f81a66d34..03014224ef13 100644
>> --- a/drivers/vhost/vhost.c
>> +++ b/drivers/vhost/vhost.c
>> @@ -1024,8 +1024,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
>> int type, ret;
>>
>> ret = copy_from_iter(&type, sizeof(type), from);
>> - if (ret != sizeof(type))
>> + if (ret != sizeof(type)) {
>> + ret = -EINVAL;
>> goto done;
>> + }
>>
>> switch (type) {
>> case VHOST_IOTLB_MSG:
>
> should this be EFAULT rather?
We already have "Invalid argument" returned when wrong type of vhost_msg
received, I though it would be fine to return same thing if we have
wrong size of vhost_msg.
When we return "Bad address" because of vhost_process_iotlb_msg fail, it
is because our vhost_dev has no ->iotlb so our problem is not connected
to the data passed from userspace but with the state of vhost_dev.
So I like EINVAL more in these two cases.
>
>> @@ -1044,8 +1046,10 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
>>
>> iov_iter_advance(from, offset);
>> ret = copy_from_iter(&msg, sizeof(msg), from);
>> - if (ret != sizeof(msg))
>> + if (ret != sizeof(msg)) {
>> + ret = -EINVAL;
>> goto done;
>> + }
>> if (vhost_process_iotlb_msg(dev, &msg)) {
>> ret = -EFAULT;
>> goto done;
>
> This too?
>
>> --
>> 2.17.1
--
Best regards, Tikhomirov Pavel
Software Developer, Virtuozzo.
From: Pavel Tikhomirov <[email protected]>
Date: Thu, 13 Dec 2018 17:53:50 +0300
> We've failed to copy and process vhost_iotlb_msg so let userspace at
> least know about it. For instance before these patch the code below runs
> without any error:
...
> Signed-off-by: Pavel Tikhomirov <[email protected]>
Michael, will you be taking this in via your tree?
Thanks.
On Sat, Dec 15, 2018 at 11:46:11AM -0800, David Miller wrote:
> From: Pavel Tikhomirov <[email protected]>
> Date: Thu, 13 Dec 2018 17:53:50 +0300
>
> > We've failed to copy and process vhost_iotlb_msg so let userspace at
> > least know about it. For instance before these patch the code below runs
> > without any error:
> ...
> > Signed-off-by: Pavel Tikhomirov <[email protected]>
>
> Michael, will you be taking this in via your tree?
>
> Thanks.
Will do, thanks!