Re: [PATCH 2/2] vfio iommu type1: fix the testing of capability for remote task

[Jike Song]

On 12/22/2016 08:20 PM, Kirti Wankhede wrote:
> On 12/21/2016 9:40 PM, Jike Song wrote:
>> Before the mdev enhancement type1 iommu used capable() to test the
>> capability of current task; in the course of mdev development a
>> new requirement, testing for another task other than current, was
>> raised.  ns_capable() was used for this purpose, however it still
>> tests current, the only difference is, in a specified namespace.
>>
>> Fix it by using has_capability() instead, which tests the cap for
>> specified task in init_user_ns, the same namespace as capable().
>>
>> Cc: Alex Williamson 
>> Cc: Kirti Wankhede 
>> Cc: Gerd Hoffmann 
>> Signed-off-by: Jike Song 
>> ---
>>  drivers/vfio/vfio_iommu_type1.c | 6 ++
>>  1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio_iommu_type1.c 
>> b/drivers/vfio/vfio_iommu_type1.c
>> index f3726ba..b54aedf 100644
>> --- a/drivers/vfio/vfio_iommu_type1.c
>> +++ b/drivers/vfio/vfio_iommu_type1.c
>> @@ -394,8 +394,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, 
>> unsigned long vaddr,
>>long npage, unsigned long *pfn_base)
>>  {
>>  unsigned long limit;
>> -bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
>> -   CAP_IPC_LOCK);
>> +bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
> 
> 
> Hi Jike,
> 
> Alex's patch already changes this to capable(), you need to resolve.
> https://lkml.org/lkml/2016/12/20/490
> 
> You need to do only below change, which looks fine to me.
> 

Thanks for the point, will change it in v2.  However, that will probably be
after patch 1/2 accepted, otherwise we get undefined symbols.

--
Thanks,
Jike

>>  struct mm_struct *mm;
>>  long ret, i = 0, lock_acct = 0;
>>  bool rsvd;
>> @@ -491,8 +490,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, 
>> unsigned long vaddr,
>>unsigned long *pfn_base, bool do_accounting)
>>  {
>>  unsigned long limit;
>> -bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
>> -   CAP_IPC_LOCK);
>> +bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
>>  struct mm_struct *mm;
>>  int ret;
>>  bool rsvd;
>>

Re: [PATCH 2/2] vfio iommu type1: fix the testing of capability for remote task

[Jike Song]

On 12/22/2016 08:20 PM, Kirti Wankhede wrote:
> On 12/21/2016 9:40 PM, Jike Song wrote:
>> Before the mdev enhancement type1 iommu used capable() to test the
>> capability of current task; in the course of mdev development a
>> new requirement, testing for another task other than current, was
>> raised.  ns_capable() was used for this purpose, however it still
>> tests current, the only difference is, in a specified namespace.
>>
>> Fix it by using has_capability() instead, which tests the cap for
>> specified task in init_user_ns, the same namespace as capable().
>>
>> Cc: Alex Williamson 
>> Cc: Kirti Wankhede 
>> Cc: Gerd Hoffmann 
>> Signed-off-by: Jike Song 
>> ---
>>  drivers/vfio/vfio_iommu_type1.c | 6 ++
>>  1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio_iommu_type1.c 
>> b/drivers/vfio/vfio_iommu_type1.c
>> index f3726ba..b54aedf 100644
>> --- a/drivers/vfio/vfio_iommu_type1.c
>> +++ b/drivers/vfio/vfio_iommu_type1.c
>> @@ -394,8 +394,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, 
>> unsigned long vaddr,
>>long npage, unsigned long *pfn_base)
>>  {
>>  unsigned long limit;
>> -bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
>> -   CAP_IPC_LOCK);
>> +bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
> 
> 
> Hi Jike,
> 
> Alex's patch already changes this to capable(), you need to resolve.
> https://lkml.org/lkml/2016/12/20/490
> 
> You need to do only below change, which looks fine to me.
> 

Thanks for the point, will change it in v2.  However, that will probably be
after patch 1/2 accepted, otherwise we get undefined symbols.

--
Thanks,
Jike

>>  struct mm_struct *mm;
>>  long ret, i = 0, lock_acct = 0;
>>  bool rsvd;
>> @@ -491,8 +490,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, 
>> unsigned long vaddr,
>>unsigned long *pfn_base, bool do_accounting)
>>  {
>>  unsigned long limit;
>> -bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
>> -   CAP_IPC_LOCK);
>> +bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
>>  struct mm_struct *mm;
>>  int ret;
>>  bool rsvd;
>>

Re: [PATCH 2/2] vfio iommu type1: fix the testing of capability for remote task

[Kirti Wankhede]

On 12/21/2016 9:40 PM, Jike Song wrote:
> Before the mdev enhancement type1 iommu used capable() to test the
> capability of current task; in the course of mdev development a
> new requirement, testing for another task other than current, was
> raised.  ns_capable() was used for this purpose, however it still
> tests current, the only difference is, in a specified namespace.
> 
> Fix it by using has_capability() instead, which tests the cap for
> specified task in init_user_ns, the same namespace as capable().
> 
> Cc: Alex Williamson 
> Cc: Kirti Wankhede 
> Cc: Gerd Hoffmann 
> Signed-off-by: Jike Song 
> ---
>  drivers/vfio/vfio_iommu_type1.c | 6 ++
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index f3726ba..b54aedf 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -394,8 +394,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, 
> unsigned long vaddr,
> long npage, unsigned long *pfn_base)
>  {
>   unsigned long limit;
> - bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
> -CAP_IPC_LOCK);
> + bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);


Hi Jike,

Alex's patch already changes this to capable(), you need to resolve.
https://lkml.org/lkml/2016/12/20/490

You need to do only below change, which looks fine to me.

>   struct mm_struct *mm;
>   long ret, i = 0, lock_acct = 0;
>   bool rsvd;
> @@ -491,8 +490,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, 
> unsigned long vaddr,
> unsigned long *pfn_base, bool do_accounting)
>  {
>   unsigned long limit;
> - bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
> -CAP_IPC_LOCK);
> + bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
>   struct mm_struct *mm;
>   int ret;
>   bool rsvd;
> 


Thanks,
Kirti

Re: [PATCH 2/2] vfio iommu type1: fix the testing of capability for remote task

[Kirti Wankhede]

On 12/21/2016 9:40 PM, Jike Song wrote:
> Before the mdev enhancement type1 iommu used capable() to test the
> capability of current task; in the course of mdev development a
> new requirement, testing for another task other than current, was
> raised.  ns_capable() was used for this purpose, however it still
> tests current, the only difference is, in a specified namespace.
> 
> Fix it by using has_capability() instead, which tests the cap for
> specified task in init_user_ns, the same namespace as capable().
> 
> Cc: Alex Williamson 
> Cc: Kirti Wankhede 
> Cc: Gerd Hoffmann 
> Signed-off-by: Jike Song 
> ---
>  drivers/vfio/vfio_iommu_type1.c | 6 ++
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index f3726ba..b54aedf 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -394,8 +394,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, 
> unsigned long vaddr,
> long npage, unsigned long *pfn_base)
>  {
>   unsigned long limit;
> - bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
> -CAP_IPC_LOCK);
> + bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);


Hi Jike,

Alex's patch already changes this to capable(), you need to resolve.
https://lkml.org/lkml/2016/12/20/490

You need to do only below change, which looks fine to me.

>   struct mm_struct *mm;
>   long ret, i = 0, lock_acct = 0;
>   bool rsvd;
> @@ -491,8 +490,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, 
> unsigned long vaddr,
> unsigned long *pfn_base, bool do_accounting)
>  {
>   unsigned long limit;
> - bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
> -CAP_IPC_LOCK);
> + bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
>   struct mm_struct *mm;
>   int ret;
>   bool rsvd;
> 


Thanks,
Kirti

[PATCH 2/2] vfio iommu type1: fix the testing of capability for remote task

[Jike Song]

Before the mdev enhancement type1 iommu used capable() to test the
capability of current task; in the course of mdev development a
new requirement, testing for another task other than current, was
raised.  ns_capable() was used for this purpose, however it still
tests current, the only difference is, in a specified namespace.

Fix it by using has_capability() instead, which tests the cap for
specified task in init_user_ns, the same namespace as capable().

Cc: Alex Williamson 
Cc: Kirti Wankhede 
Cc: Gerd Hoffmann 
Signed-off-by: Jike Song 
---
 drivers/vfio/vfio_iommu_type1.c | 6 ++
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index f3726ba..b54aedf 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -394,8 +394,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, 
unsigned long vaddr,
  long npage, unsigned long *pfn_base)
 {
unsigned long limit;
-   bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
-  CAP_IPC_LOCK);
+   bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
struct mm_struct *mm;
long ret, i = 0, lock_acct = 0;
bool rsvd;
@@ -491,8 +490,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, 
unsigned long vaddr,
  unsigned long *pfn_base, bool do_accounting)
 {
unsigned long limit;
-   bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
-  CAP_IPC_LOCK);
+   bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
struct mm_struct *mm;
int ret;
bool rsvd;
-- 
2.4.4.488.gdf97e5d

[PATCH 2/2] vfio iommu type1: fix the testing of capability for remote task

[Jike Song]

Before the mdev enhancement type1 iommu used capable() to test the
capability of current task; in the course of mdev development a
new requirement, testing for another task other than current, was
raised.  ns_capable() was used for this purpose, however it still
tests current, the only difference is, in a specified namespace.

Fix it by using has_capability() instead, which tests the cap for
specified task in init_user_ns, the same namespace as capable().

Cc: Alex Williamson 
Cc: Kirti Wankhede 
Cc: Gerd Hoffmann 
Signed-off-by: Jike Song 
---
 drivers/vfio/vfio_iommu_type1.c | 6 ++
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index f3726ba..b54aedf 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -394,8 +394,7 @@ static long vfio_pin_pages_remote(struct vfio_dma *dma, 
unsigned long vaddr,
  long npage, unsigned long *pfn_base)
 {
unsigned long limit;
-   bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
-  CAP_IPC_LOCK);
+   bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
struct mm_struct *mm;
long ret, i = 0, lock_acct = 0;
bool rsvd;
@@ -491,8 +490,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, 
unsigned long vaddr,
  unsigned long *pfn_base, bool do_accounting)
 {
unsigned long limit;
-   bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
-  CAP_IPC_LOCK);
+   bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
struct mm_struct *mm;
int ret;
bool rsvd;
-- 
2.4.4.488.gdf97e5d