[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH] x86: fix bug_line()
On 11/10/2013 16:25, "Jan Beulich" <JBeulich@xxxxxxxx> wrote: > Due to the packing into a bit field together with a relocated field, > the computation can overflow when the relocated field ends up getting a > negative value stored. Hence it isn't sufficient to correct the value > by 1 in this case, but we also need to mask the result to the width of > the original bit field. > > Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> Acked-by: Keir Fraser <keir@xxxxxxx> > --- a/xen/include/asm-x86/bug.h > +++ b/xen/include/asm-x86/bug.h > @@ -15,9 +15,11 @@ struct bug_frame { > > #define bug_loc(b) ((const void *)(b) + (b)->loc_disp) > #define bug_ptr(b) ((const void *)(b) + (b)->ptr_disp) > -#define bug_line(b) ((((b)->line_hi + ((b)->loc_disp < 0)) << > \ > +#define bug_line(b) (((((b)->line_hi + ((b)->loc_disp < 0)) & > \ > + ((1 << BUG_LINE_HI_WIDTH) - 1)) << > \ > BUG_LINE_LO_WIDTH) + > \ > - (b)->line_lo + ((b)->ptr_disp < 0)) > + (((b)->line_lo + ((b)->ptr_disp < 0)) & > \ > + ((1 << BUG_LINE_LO_WIDTH) - 1))) > #define bug_msg(b) ((const char *)(b) + (b)->msg_disp[1]) > > #define BUGFRAME_run_fn 0 > > > _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |