Messages in this thread | | | Date | Thu, 5 Mar 2015 12:34:17 -0800 (PST) | From | David Rientjes <> | Subject | Re: [PATCH] mm: pagewalk: prevent positive return value of walk_page_test() from being passed to callers (Re: [PATCH] mm: fix do_mbind return value) |
| |
On Thu, 5 Mar 2015, Naoya Horiguchi wrote:
> walk_page_test() is purely pagewalk's internal stuff, and its positive return > values are not intended to be passed to the callers of pagewalk. However, in > the current code if the last vma in the do-while loop in walk_page_range() > happens to return a positive value, it leaks outside walk_page_range(). > So the user visible effect is invalid/unexpected return value (according to > the reporter, mbind() causes it.) > > This patch fixes it simply by reinitializing the return value after checked. > > Another exposed interface, walk_page_vma(), already returns 0 for such cases > so no problem. > > Fixes: 6f4576e3687b ("mempolicy: apply page table walker on queue_pages_range()") > Reported-by: Kazutomo Yoshii <kazutomo.yoshii@gmail.com> > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: David Rientjes <rientjes@google.com>
This is exactly what I had in mind, thanks for fixing it up so fast!
| |