drivers/char/ppdev.c: fix information leak to userland

Structure par_timeout is copied to userland with some padding fields
unitialized.  Field tv_usec has type __kernel_suseconds_t, it differs from
tv_sec's type on some architectures.  It leads to leaking of stack memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Vasiliy Kulikov 2010-10-27 15:34:21 -07:00 коммит произвёл Linus Torvalds
Родитель 19714a8af8
Коммит b9b1134260
1 изменённых файлов: 1 добавлений и 0 удалений

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@ -613,6 +613,7 @@ static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case PPGETTIME:
to_jiffies = pp->pdev->timeout;
memset(&par_timeout, 0, sizeof(par_timeout));
par_timeout.tv_sec = to_jiffies / HZ;
par_timeout.tv_usec = (to_jiffies % (long)HZ) * (1000000/HZ);
if (copy_to_user (argp, &par_timeout, sizeof(struct timeval)))