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.zhangjian@linaro.org
Reviewed-by: Arnd Bergmann arnd@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