On 06/27/2015 08:51 PM, Patrick Donnelly wrote: > This fixes a bug where a process can set the foreground process group to its > pid even if its pid is not a valid pgrp. > > Signed-off-by: Patrick Donnelly <batr...@batbytes.com> > --- > drivers/tty/tty_io.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c > index fbb55db..01b4769 100644 > --- a/drivers/tty/tty_io.c > +++ b/drivers/tty/tty_io.c > @@ -2579,6 +2579,9 @@ static int tiocspgrp(struct tty_struct *tty, struct > tty_struct *real_tty, pid_t > retval = -ESRCH; > if (!pgrp) > goto out_unlock; > + retval = -EINVAL; > + if (!pid_task(pgrp, PIDTYPE_PGID)) > + goto out_unlock;
This change implies that the sequence in session_of_pgrp() that specifically checks for pid_task(pgrp, PIDTYPE_PGID) == NULL is not doing anything useful. However, that hypothesis is directly contradicted by the comment above session_of_pgrp() "* This checks not only the pgrp, but falls back on the pid if no * satisfactory pgrp is found. I dunno - gdb doesn't work correctly * without this..." Regards, Peter Hurley > retval = -EPERM; > if (session_of_pgrp(pgrp) != task_session(current)) > goto out_unlock; > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
