Em Mon, Sep 16, 2019 at 01:44:40AM +0900, Masami Hiramatsu escreveu:
> Since add_probe_trace_event() can reuse tf->tevs[i] after
> calling clear_probe_trace_event(), this can make perf-probe
> crash if the 1st attempt of probe event finding fails to find
> an event argument, and the 2nd attempt fails to find probe point.
>
> E.g.
> $ perf probe -D "task_pid_nr tsk"
> Failed to find 'tsk' in this function.
> Failed to get entry address of warn_bad_vsyscall
> Segmentation fault (core dumped)
Thanks, tested and applied!
- Arnaldo
>
> Fixes: 092b1f0b5f9f ("perf probe: Clear probe_trace_event when
> add_probe_trace_event() fails")
> Signed-off-by: Masami Hiramatsu <[email protected]>
> Cc: Wang Nan <[email protected]>
> ---
> tools/perf/util/probe-event.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index b8e0967c5c21..91cab5f669d2 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -2331,6 +2331,7 @@ void clear_probe_trace_event(struct probe_trace_event
> *tev)
> }
> }
> zfree(&tev->args);
> + tev->nargs = 0;
> }
>
> struct kprobe_blacklist_node {
--
- Arnaldo
