public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH] perf: report: don't call map__kmap if map is NULL.
@ 2015-04-08 10:59 Wang Nan
  2015-04-08 12:56 ` Arnaldo Carvalho de Melo
  2015-04-08 15:15 ` [tip:perf/core] perf report: Don't " tip-bot for Wang Nan
  0 siblings, 2 replies; 3+ messages in thread
From: Wang Nan @ 2015-04-08 10:59 UTC (permalink / raw)
  To: acme, jolsa, jolsa, adrian.hunter; +Cc: mingo, lizefan, linux-kernel, pi3orama

report__warn_kptr_restrict() calls map__kmap(kernel_map) before
checking kernel_map againest NULL. Which is dangerous, since
map__kmap() will return a invalid and not NULL address. It will trigger
a warning message in map__kmap() after patch "perf: kmaps: enforce
usage of kmaps to protect futher bugs."

This patch fixes it by adding the missing checking.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
---
 tools/perf/builtin-report.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index b5b2ad4..476cdf7 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -347,7 +347,7 @@ static int perf_evlist__tty_browse_hists(struct perf_evlist *evlist,
 static void report__warn_kptr_restrict(const struct report *rep)
 {
 	struct map *kernel_map = rep->session->machines.host.vmlinux_maps[MAP__FUNCTION];
-	struct kmap *kernel_kmap = map__kmap(kernel_map);
+	struct kmap *kernel_kmap = kernel_map ? map__kmap(kernel_map) : NULL;
 
 	if (kernel_map == NULL ||
 	    (kernel_map->dso->hit &&
-- 
1.8.3.4


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2015-04-08 15:15 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-04-08 10:59 [PATCH] perf: report: don't call map__kmap if map is NULL Wang Nan
2015-04-08 12:56 ` Arnaldo Carvalho de Melo
2015-04-08 15:15 ` [tip:perf/core] perf report: Don't " tip-bot for Wang Nan

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox