lkml.org 
[lkml]   [2013]   [Oct]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] core: Catch overflows in do_div() function
From
Date
On Tue, 2013-10-08 at 18:45 +0200, Richard Weinberger wrote:
> 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.

Add __builtin_constant_p(base).




\
 
 \ /
  Last update: 2013-10-09 11:21    [W:0.121 / U:0.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site