On Thu, Jan 7, 2016 at 4:31 PM, Benjamin LaHaise <bcrl@xxxxxxxxx> wrote: > On Thu, Jan 07, 2016 at 10:12:02AM +0100, Dmitry Vyukov wrote: > ... >> Sorry, but the following program still prints -9223372036562067969. I >> think timespec_valid check will do. > > Ah, right. Yes, using timespec_valid() instead of timespec_valid_strict() > as initially proposed will address my concerns. Updated commit below. > > -ben > -- > "Thought is the essence of where you are now." > > commit 3a55c535cf3836257434518bd6bc11464c493492 > Author: Benjamin LaHaise <bcrl@xxxxxxxxx> > Date: Thu Jan 7 10:25:44 2016 -0500 > > aio: handle integer overflow in io_getevents() timespec usage > > Dmitry Vyukov reported an integer overflow in io_getevents() when > running a fuzzer. Upon investigation, the triggers appears to be that > an invalid value for the tv_sec or tv_nsec was passed in which is not > handled by timespec_to_ktime(). This patch fixes that by making > io_getevents() return -EINVAL when timespec_valid() checks fail. We > use timespec_valid() instead of timespec_valid_strict() to avoid issues > caused by userspace not knowing the cutoff for KTIME_SEC_MAX. > > Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> > Signed-off-by: Benjamin LaHaise <bcrl@xxxxxxxxx> > > diff --git a/fs/aio.c b/fs/aio.c > index 155f842..d161a2f 100644 > --- a/fs/aio.c > +++ b/fs/aio.c > @@ -1269,6 +1269,8 @@ static long read_events(struct kioctx *ctx, long min_nr, long nr, > > if (unlikely(copy_from_user(&ts, timeout, sizeof(ts)))) > return -EFAULT; > + if (!timespec_valid()) pass ts to the function > + return -EINVAL; > > until = timespec_to_ktime(ts); > } -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
