Re: [PATCH] cxl: Fix error path on bad ioctl

[Michael Ellerman]

Frederic Barrat  writes:

> Le 06/06/2017 à 11:20, Michael Ellerman a écrit :
>> Frederic Barrat  writes:
>> 
>>> Fix error path if we can't copy user structure on
>>> CXL_IOCTL_START_WORK ioctl.
>> 
>> To be clear the error is that returning via the out label will unlock
>> cxl->status_mutex, which has not been locked.
>> 
>> Please spell it out for me :)
>> 
>> This should be:
>> 
>>Fixes: 0712dc7e73e5 ("cxl: Fix issues when unmapping contexts")
>> 
>> Am I right?
>
> That's correct. I'm about to send a v2 to address Vaibhav's comment and 
> I'll fix the above as well.

Thanks.

cheers

Re: [PATCH] cxl: Fix error path on bad ioctl

[Frederic Barrat]

Le 06/06/2017 à 11:20, Michael Ellerman a écrit :

Frederic Barrat  writes:


Fix error path if we can't copy user structure on
CXL_IOCTL_START_WORK ioctl.


To be clear the error is that returning via the out label will unlock
cxl->status_mutex, which has not been locked.

Please spell it out for me :)

This should be:

   Fixes: 0712dc7e73e5 ("cxl: Fix issues when unmapping contexts")

Am I right?



That's correct. I'm about to send a v2 to address Vaibhav's comment and 
I'll fix the above as well.


Thanks,

  Fred




cheers


diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c
index 17b433f1ce23..caa44adfa60e 100644
--- a/drivers/misc/cxl/file.c
+++ b/drivers/misc/cxl/file.c
@@ -160,10 +160,8 @@ static long afu_ioctl_start_work(struct cxl_context *ctx,
/* Do this outside the status_mutex to avoid a circular dependency with
 * the locking in cxl_mmap_fault() */
if (copy_from_user(, uwork,
-  sizeof(struct cxl_ioctl_start_work))) {
-   rc = -EFAULT;
-   goto out;
-   }
+  sizeof(struct cxl_ioctl_start_work)))
+   return -EFAULT;
  
  	mutex_lock(>status_mutex);

if (ctx->status != OPENED) {
--
2.11.0

Re: [PATCH] cxl: Fix error path on bad ioctl

[Michael Ellerman]

Frederic Barrat  writes:

> Fix error path if we can't copy user structure on
> CXL_IOCTL_START_WORK ioctl.

To be clear the error is that returning via the out label will unlock
cxl->status_mutex, which has not been locked.

Please spell it out for me :)

This should be:

  Fixes: 0712dc7e73e5 ("cxl: Fix issues when unmapping contexts")

Am I right?

cheers

> diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c
> index 17b433f1ce23..caa44adfa60e 100644
> --- a/drivers/misc/cxl/file.c
> +++ b/drivers/misc/cxl/file.c
> @@ -160,10 +160,8 @@ static long afu_ioctl_start_work(struct cxl_context *ctx,
>   /* Do this outside the status_mutex to avoid a circular dependency with
>* the locking in cxl_mmap_fault() */
>   if (copy_from_user(, uwork,
> -sizeof(struct cxl_ioctl_start_work))) {
> - rc = -EFAULT;
> - goto out;
> - }
> +sizeof(struct cxl_ioctl_start_work)))
> + return -EFAULT;
>  
>   mutex_lock(>status_mutex);
>   if (ctx->status != OPENED) {
> -- 
> 2.11.0

Re: [PATCH] cxl: Fix error path on bad ioctl

[Andrew Donnellan]

On 03/06/17 02:15, Frederic Barrat wrote:

Fix error path if we can't copy user structure on
CXL_IOCTL_START_WORK ioctl.

Signed-off-by: Frederic Barrat 
Cc: sta...@vger.kernel.org


Reviewed-by: Andrew Donnellan 

--
Andrew Donnellan  OzLabs, ADL Canberra
andrew.donnel...@au1.ibm.com  IBM Australia Limited

Re: [PATCH] cxl: Fix error path on bad ioctl

[Vaibhav Jain]

Hi Fred,

Good catch.

Frederic Barrat  writes:

> Fix error path if we can't copy user structure on
> CXL_IOCTL_START_WORK ioctl.
>
> Signed-off-by: Frederic Barrat 
> Cc: sta...@vger.kernel.org
> ---
>  drivers/misc/cxl/file.c | 6 ++
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c
> index 17b433f1ce23..caa44adfa60e 100644
> --- a/drivers/misc/cxl/file.c
> +++ b/drivers/misc/cxl/file.c
> @@ -160,10 +160,8 @@ static long afu_ioctl_start_work(struct cxl_context *ctx,
>   /* Do this outside the status_mutex to avoid a circular dependency with
>* the locking in cxl_mmap_fault() */
>   if (copy_from_user(, uwork,
> -sizeof(struct cxl_ioctl_start_work))) {
> - rc = -EFAULT;
> - goto out;
> - }
> +sizeof(struct cxl_ioctl_start_work)))

Bike-shedding a bit, but
s/sizeof(struct cxl_ioctl_start_work)))/sizeof(work)/
would look much cleaner


Reviewed-by: Vaibhav Jain 

[PATCH] cxl: Fix error path on bad ioctl

[Frederic Barrat]

Fix error path if we can't copy user structure on
CXL_IOCTL_START_WORK ioctl.

Signed-off-by: Frederic Barrat 
Cc: sta...@vger.kernel.org
---
 drivers/misc/cxl/file.c | 6 ++
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c
index 17b433f1ce23..caa44adfa60e 100644
--- a/drivers/misc/cxl/file.c
+++ b/drivers/misc/cxl/file.c
@@ -160,10 +160,8 @@ static long afu_ioctl_start_work(struct cxl_context *ctx,
/* Do this outside the status_mutex to avoid a circular dependency with
 * the locking in cxl_mmap_fault() */
if (copy_from_user(, uwork,
-  sizeof(struct cxl_ioctl_start_work))) {
-   rc = -EFAULT;
-   goto out;
-   }
+  sizeof(struct cxl_ioctl_start_work)))
+   return -EFAULT;
 
mutex_lock(>status_mutex);
if (ctx->status != OPENED) {
-- 
2.11.0