Messages in this thread | | | Date | Tue, 8 Oct 2013 18:45:21 +0200 | Subject | Re: [PATCH] core: Catch overflows in do_div() function | From | Richard Weinberger <> |
| |
On Tue, Oct 8, 2013 at 6:18 PM, Joe Perches <joe@perches.com> wrote: > On Tue, 2013-10-08 at 09:10 -0700, Anatol Pomozov wrote: >> If second parameter passed to this function was 64 then it silently >> truncates to 32 bits. Catch such situation. > [] >> diff --git a/include/asm-generic/div64.h b/include/asm-generic/div64.h > [] >> @@ -25,6 +26,7 @@ >> # define do_div(n,base) ({ \ >> uint32_t __base = (base); \ >> uint32_t __rem; \ >> + BUG_ON(sizeof(base) > 4 && base >= (1UL<<32)); \ > > I think this would be better as a BUILD_BUG_ON
No. BUILD_BUG_ON works only for constants.
Anatol, have you tested whether your change increases the kernel size?
-- Thanks, //richard
| |