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

Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

kernel os linux

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>

authored by

Vasiliy Kulikov and committed by

Linus Torvalds 15 years ago b9b11342 19714a8a

1 changed file

expand all

drivers

char

ppdev.c

drivers/char/ppdev.c

··· 613 613 614 614 case PPGETTIME: 615 615 to_jiffies = pp->pdev->timeout; 616 + memset(&par_timeout, 0, sizeof(par_timeout)); 616 617 par_timeout.tv_sec = to_jiffies / HZ; 617 618 par_timeout.tv_usec = (to_jiffies % (long)HZ) * (1000000/HZ); 618 619 if (copy_to_user (argp, &par_timeout, sizeof(struct timeval)))