Messages in this thread |  | | Date | Fri, 10 Feb 2012 14:49:17 +0100 | Subject | Re: [PATCH] perf: add sanity check on addr in symbol__inc_addr_samples() | From | Stephane Eranian <> |
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On Fri, Feb 10, 2012 at 2:46 PM, Arnaldo Carvalho de Melo <acme@redhat.com> wrote: > 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) > Fine with me. It makes more sense.
> - 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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