Re: [PATCH] perf: check if address is in range

From: Arnaldo Carvalho de Melo
Date: Fri Jan 13 2012 - 07:25:53 EST


Em Thu, Jan 12, 2012 at 10:39:38PM +0200, Sorin Dumitru escreveu:
> When addr isn't in the [sym->start,sym->end] range offset
> will be a very big value, giving us a segfault when we do:
> h->addr[offset]++
> Fix this by checking that addr is in the correct range.

Is this against what tree? Can you please provide a backtrace of when
this happens?

I ask this because this is a kind of BUG_ON() situation, one shouldn't
get to this point if the address is not within that symbol.

- Arnaldo

> Signed-off-by: Sorin Dumitru <dumitru.sorin87@xxxxxxxxx>
> ---
> tools/perf/util/annotate.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 011ed26..4ddc55f 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->start || addr >= sym->end)
> return 0;
>
> offset = addr - sym->start;
> --
> 1.7.8.3
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