On 02/25, Serge E. Hallyn wrote: > > Quoting Oleg Nesterov ([EMAIL PROTECTED]): > > kill_pid_info_as_uid() is solely used by drivers/usb/core/. The original > > "[PATCH] Fix signal sending in usbdevio on async URB completion" commit > > 46113830a18847cff8da73005e57bc49c2f95a56 was right, but nowadays we use > > struct pid and this solves most of the addressed problems. > > > > It would be nice to use kill_pid_info() instead, but we can't because USB > > uses .si_code = SI_ASYNCIO which fools SI_FROMUSER() and thus security > > checks. > > > > I think we should omit the permission checks completely, the task which does > > ioctl(USBDEVFS_SUBMITURB) explicitly asks to send the signal to it, we > > should > > not deny the signal even if the task changes its credentials in any way. > > > > For now, we can remove security_task_kill(). It is bogus, the signal has > > come > > from kernel. > > Ok, could you augment the comment above > kernel/signal.c:kill_pid_info_as_uid() to say that it is only called > from within the usb subsystem?
OK, will do a bit later. I still hope we can kill this helper or at least cleanup it further. What we need in fact is kill_pid_info_skip_check_kill_permission(), and only because USB uses SI_ASYNCIO < 0. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
