[PATCH 1/2] perf probe: Only call probe_file__get_events() when fd is valid

From: Wang Nan
Date: Thu Nov 05 2015 - 08:20:39 EST


In system with kprobe enabled but uprobe turned off, 'perf probe -d'
causes segfault because it calls probe_file__get_events() with a
negative fd (when deleting uprobe events).

This patch validates fds before calling probe_file__get_events().

Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/builtin-probe.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 132afc9..861aa89 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -384,7 +384,11 @@ static int perf_del_probe_events(struct strfilter *filter)
goto out;
}

- ret = probe_file__get_events(kfd, filter, klist);
+ if (kfd < 0)
+ ret = -ENOENT;
+ else
+ ret = probe_file__get_events(kfd, filter, klist);
+
if (ret == 0) {
strlist__for_each(ent, klist)
pr_info("Removed event: %s\n", ent->s);
@@ -394,7 +398,11 @@ static int perf_del_probe_events(struct strfilter *filter)
goto error;
}

- ret2 = probe_file__get_events(ufd, filter, ulist);
+ if (ufd < 0)
+ ret2 = -ENOENT;
+ else
+ ret2 = probe_file__get_events(ufd, filter, ulist);
+
if (ret2 == 0) {
strlist__for_each(ent, ulist)
pr_info("Removed event: %s\n", ent->s);
--
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/