Messages in this thread Patch in this message | | | Date | Fri, 10 Feb 2012 11:46:46 -0200 | From | Arnaldo Carvalho de Melo <> | Subject | Re: [PATCH] perf: add sanity check on addr in symbol__inc_addr_samples() |
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Em Thu, Feb 09, 2012 at 03:53:14PM +0100, Stephane Eranian escreveu: > On Thu, Feb 9, 2012 at 3:48 PM, Arnaldo Carvalho de Melo > <acme@redhat.com> wrote: > > Em Thu, Feb 09, 2012 at 11:30:16AM +0100, Stephane Eranian escreveu: > >> > >> Check the value of addr against the bounds of the symbol. > >> This is needed given we compute an offset: > >> offset = addr - sym->start > >> > >> And we don't want the offset to become negative. > > > > I'll try and add a debug option to show the backtrace and values of > > addr, sym, etc, so that we can fix the real problem.
> > I.e. this function shouldn't be receiving any such invalid addresses, as > > the symbol lookup was done, the symbol was found to be this one, then > > why it would be out of bounds at this point?!
> I tend to agree with you on this. But then I don't see why the first test > was there.
Its wrong as well, we should leave it there, together with the new test, but as:
BUG_ON(addr >= sym->end || addr < sym->start)
- Arnaldo > > - Arnaldo > > > >> Signed-off-by: Stephane Eranian <eranian@google.com> > >> > >> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c > >> index 011ed26..8248d80 100644 > >> --- a/tools/perf/util/annotate.c > >> +++ b/tools/perf/util/annotate.c > >> @@ -64,7 +64,7 @@ int symbol__inc_addr_samples(struct symbol *sym, struct map *map, > >> > >> pr_debug3("%s: addr=%#" PRIx64 "\n", __func__, map->unmap_ip(map, addr)); > >> > >> - if (addr >= sym->end) > >> + if (addr >= sym->end || addr < sym->start) > >> return 0; > >> > >> offset = addr - sym->start; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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