Hi, Sudip
On 12/30/2015 07:16 PM, Sudip Mukherjee wrote:
> On Fri, Dec 18, 2015 at 12:12:05AM +0100, Arnd Bergmann wrote:
>> On Thursday 17 December 2015 17:58:52 Bamvor Jian Zhang wrote:
>>> The arg of ioctl in ppdev is the pointer of integer except the
>>> timeval in PPSETTIME, PPGETTIME. Different size of timeval
>>> is already supported by the previous patches. So, it is safe
>>> to add compat support.
>>>
>>> Signed-off-by: Bamvor Jian Zhang <bamvor.zhangj...@linaro.org>
>>>
>>
>> Reviewed-by: Arnd Bergmann <a...@arndb.de>
>>
>> (I think I replied with the reviewed-by tag before to this patch)
>
> I was testing this series today. And it is breaking my userspace code. I
> am attaching my userspace code for you to check. Its very simple
> userspace code:
> 1: open
> 2: ioctl to claim
> 3: ioctl - PPGETTIME
> 4: ioctl - PPSETTIME
> 5: ioctl - PPGETTIME
> 6: ioctl - release
> 7: close
>
> Without this series it works as expected.
>
> With this series applied, the userspace code prints the error message:
> PPNEGOT: Bad address
>
> I traced it with strace and:
> ioctl(3, PPGETTIME, 0xbfe91508) = -1 EFAULT (Bad address)
Thanks for your testing. It seems that I misuse the parameters. Could
you please apply the following patch and try it again?
There is no parport in my computer, Thanks.
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c
index 31bc7b7..9e98d01 100644
--- a/drivers/char/ppdev.c
+++ b/drivers/char/ppdev.c
@@ -636,7 +636,7 @@ static int pp_do_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
if ((time32[0] < 0) || (time32[1] < 0))
return -EINVAL;
- if (copy_to_user(time32, argp, sizeof(time32)))
+ if (copy_to_user(argp, time32, sizeof(time32)))
return -EFAULT;
return 0;
@@ -648,7 +648,7 @@ static int pp_do_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
if ((time64[0] < 0) || (time64[1] < 0))
return -EINVAL;
- if (copy_to_user(time64, argp, sizeof(time64)))
+ if (copy_to_user(argp, time64, sizeof(time64)))
return -EFAULT;
return 0;
Regards
Bamvor
>
> regards
> sudip
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
