On Mon, Jun 29, 2015 at 7:23 AM, Bamvor Zhang Jian bamvor.zhangjian@linaro.org wrote:
Add compat ioctl in ppdev in order to solve the y2038 issue in later patch. This patch simply add pp_do_ioctl to compat_ioctl, because I found that all the ioctl access the arg as a pointer.
Signed-off-by: Bamvor Zhang Jian bamvor.zhangjian@linaro.org
drivers/char/ppdev.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c index ae0b42b..9207658 100644 --- a/drivers/char/ppdev.c +++ b/drivers/char/ppdev.c @@ -69,6 +69,7 @@ #include <linux/ppdev.h> #include <linux/mutex.h> #include <linux/uaccess.h> +#include <linux/compat.h>
#define PP_VERSION "ppdev: user-space parallel port driver" #define CHRDEV "ppdev" @@ -635,6 +636,11 @@ static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return ret; }
+static long pp_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{
return pp_ioctl(file, cmd, (unsigned long)compat_ptr(arg));+}
static int pp_open (struct inode * inode, struct file * file) { unsigned int minor = iminor(inode); @@ -744,6 +750,9 @@ static const struct file_operations pp_fops = { .write = pp_write, .poll = pp_poll, .unlocked_ioctl = pp_ioctl, +#ifdef CONFIG_COMPAT
.compat_ioctl = pp_compat_ioctl,+#endif
Does adding this patch w/o the following patch break 32bit apps using this on 64bit kernels?
thanks -john