On Fri, Oct 6, 2017 at 6:20 PM, Jia-Ju Bai <baijiaju1990@xxxxxxx> wrote: > > To fix it, GFP_KERNEL is replaced with GFP_ATOMIC. > This bug is found by my static analysis tool and my code review. I'm not saying your patch is wrong, but it's a shame that we do that extra allocation in match_number() and match_u64int(), and that we don't have anything that is just size-limited. And there really isn't anything saying that we shouldn't do the same silly thing to match_u64int(). Maybe we don't have any actual users that need it for now, but still.. Oh well. I do wonder if we shouldn't just use something like "skip leading zeroes, copy to size-limited stack location instead" because the input length really *is* limited once you skip leading zeroes (and whatever base marker we have). We might have at most a 64-bit value in octal, so 22 bytes max. But I guess just changing the two GFP_KERNEL's to GFP_ATOMIC is much simpler. Linus