2016-10-24 10:47:23

by Colin King

Subject: [PATCH] ARC: return -EFAULT on failed access_ok for arc_usr_cmpxchg syscall

From: Colin Ian King <[email protected]>

arc_usr_cmpxchg currently returns an uninitialized value in ret
on a failed access_ok call. Instead, return -EFAULT.

Signed-off-by: Colin Ian King <[email protected]>
---
arch/arc/kernel/process.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index a746008..9ae3e1c 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -47,7 +47,7 @@ SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
int ret;

if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
- return ret;
+ return -EFAULT;

preempt_disable();

--
2.9.3

2016-10-24 15:57:00

by Vineet Gupta

Subject: Re: [PATCH] ARC: return -EFAULT on failed access_ok for arc_usr_cmpxchg syscall

On 10/24/2016 03:47 AM, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> arc_usr_cmpxchg currently returns an uninitialized value in ret
> on a failed access_ok call. Instead, return -EFAULT.
>
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> arch/arc/kernel/process.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
> index a746008..9ae3e1c 100644
> --- a/arch/arc/kernel/process.c
> +++ b/arch/arc/kernel/process.c
> @@ -47,7 +47,7 @@ SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
> int ret;
>
> if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
> - return ret;
> + return -EFAULT;
>
> preempt_disable();

Thx for spotting this. Since this is new code, not yet merged, do you mind if I
squash it with orig patch. I can add a Reviewed-by a SOB as you prefer.

Thx,
-Vineet

2016-10-24 15:58:48

by Colin King

Subject: Re: [PATCH] ARC: return -EFAULT on failed access_ok for arc_usr_cmpxchg syscall

On 24/10/16 16:56, Vineet Gupta wrote:
> On 10/24/2016 03:47 AM, Colin King wrote:
>> From: Colin Ian King <[email protected]>
>>
>> arc_usr_cmpxchg currently returns an uninitialized value in ret
>> on a failed access_ok call. Instead, return -EFAULT.
>>
>> Signed-off-by: Colin Ian King <[email protected]>
>> ---
>> arch/arc/kernel/process.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
>> index a746008..9ae3e1c 100644
>> --- a/arch/arc/kernel/process.c
>> +++ b/arch/arc/kernel/process.c
>> @@ -47,7 +47,7 @@ SYSCALL_DEFINE3(arc_usr_cmpxchg, int *, uaddr, int, expected, int, new)
>> int ret;
>>
>> if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
>> - return ret;
>> + return -EFAULT;
>>
>> preempt_disable();
>
> Thx for spotting this. Since this is new code, not yet merged, do you mind if I
> squash it with orig patch. I can add a Reviewed-by a SOB as you prefer.

Sure, squash it int and add me as a Reviewed-by.

Colin
>
> Thx,
> -Vineet
>
>