From 182c228ebcf1ac67a44e62236d8f7a8a9a3c5699 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 2 Apr 2014 14:48:31 +0900 Subject: [PATCH] perf probe: Fix to handle errors in line_range searching As Namhyung reported(https://lkml.org/lkml/2014/4/1/89), current perf-probe -L option doesn't handle errors in line-range searching correctly. It causes a SEGV if an error occured in the line-range searching. ---- $ perf probe -x ./perf -v -L map__load Open Debuginfo file: /home/namhyung/project/linux/tools/perf/perf fname: util/map.c, lineno:153 New line range: 153 to 2147483647 path: (null) Segmentation fault (core dumped) ---- This is because line_range_inline_cb() ignores errors from find_line_range_by_line() which means that lr->path is already freed on the error path in find_line_range_by_line(). As a result, get_real_path() accesses the lr->path and it causes a NULL pointer exception. This fixes line_range_inline_cb() to handle the error correctly, and report it to the caller. Anyway, this just fixes a possible SEGV bug, Namhyung's patch is also required. Reported-by: Namhyung Kim Signed-off-by: Masami Hiramatsu Acked-by: Namhyung Kim Cc: Arnaldo Carvalho de Melo Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20140402054831.19080.27006.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Jiri Olsa --- tools/perf/util/probe-finder.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 3bf0c8cdccb7..fae274e72fe6 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -1475,14 +1475,15 @@ static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf) static int line_range_inline_cb(Dwarf_Die *in_die, void *data) { - find_line_range_by_line(in_die, data); + int ret = find_line_range_by_line(in_die, data); /* * We have to check all instances of inlined function, because * some execution paths can be optimized out depends on the - * function argument of instances + * function argument of instances. However, if an error occurs, + * it should be handled by the caller. */ - return 0; + return ret < 0 ? ret : 0; } /* Search function definition from function name */ -- 2.39.5