2023-06-13 00:15:38

by Namhyung Kim

Subject: [PATCH 1/2] perf dwarf-aux: Fix off-by-one in die_get_varname()

The die_get_varname() returns "(unknown_type)" string if it failed to
find a type for the variable. But it had a space before the opening
parenthesis and it made the closing parenthesis cut off due to the
off-by-one in the string length (14).

Signed-off-by: Namhyung Kim <[email protected]>
---
tools/perf/util/dwarf-aux.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index e4593a71556b..1ac88b79687d 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -1103,7 +1103,7 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
ret = die_get_typename(vr_die, buf);
if (ret < 0) {
pr_debug("Failed to get type, make it unknown.\n");
- ret = strbuf_add(buf, " (unknown_type)", 14);
+ ret = strbuf_add(buf, "(unknown_type)", 14);
}

return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
--
2.41.0.162.gfafddb0af9-goog

2023-06-13 15:03:17

by Arnaldo Carvalho de Melo

Subject: Re: [PATCH 1/2] perf dwarf-aux: Fix off-by-one in die_get_varname()

Em Mon, Jun 12, 2023 at 04:41:01PM -0700, Namhyung Kim escreveu:
> The die_get_varname() returns "(unknown_type)" string if it failed to
> find a type for the variable. But it had a space before the opening
> parenthesis and it made the closing parenthesis cut off due to the
> off-by-one in the string length (14).

Thanks, applied both patches.

- Arnaldo


> Signed-off-by: Namhyung Kim <[email protected]>
> ---
> tools/perf/util/dwarf-aux.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
> index e4593a71556b..1ac88b79687d 100644
> --- a/tools/perf/util/dwarf-aux.c
> +++ b/tools/perf/util/dwarf-aux.c
> @@ -1103,7 +1103,7 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
> ret = die_get_typename(vr_die, buf);
> if (ret < 0) {
> pr_debug("Failed to get type, make it unknown.\n");
> - ret = strbuf_add(buf, " (unknown_type)", 14);
> + ret = strbuf_add(buf, "(unknown_type)", 14);
> }
>
> return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
> --
> 2.41.0.162.gfafddb0af9-goog
>

--

- Arnaldo

2023-06-13 15:16:55

by Arnaldo Carvalho de Melo

Subject: Re: [PATCH 1/2] perf dwarf-aux: Fix off-by-one in die_get_varname()

Em Mon, Jun 12, 2023 at 04:41:01PM -0700, Namhyung Kim escreveu:
> The die_get_varname() returns "(unknown_type)" string if it failed to
> find a type for the variable. But it had a space before the opening
> parenthesis and it made the closing parenthesis cut off due to the
> off-by-one in the string length (14).

Thanks, applied and added:

Fixes: 88fd633cdfa19060 ("perf probe: No need to use formatting strbuf method")

I introduced this long ago :-\

- Arnaldo

> Signed-off-by: Namhyung Kim <[email protected]>
> ---
> tools/perf/util/dwarf-aux.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
> index e4593a71556b..1ac88b79687d 100644
> --- a/tools/perf/util/dwarf-aux.c
> +++ b/tools/perf/util/dwarf-aux.c
> @@ -1103,7 +1103,7 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
> ret = die_get_typename(vr_die, buf);
> if (ret < 0) {
> pr_debug("Failed to get type, make it unknown.\n");
> - ret = strbuf_add(buf, " (unknown_type)", 14);
> + ret = strbuf_add(buf, "(unknown_type)", 14);
> }
>
> return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
> --
> 2.41.0.162.gfafddb0af9-goog