summaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorJiri Olsa <jolsa@redhat.com>2014-03-02 16:56:39 +0100
committerIngo Molnar <mingo@kernel.org>2014-03-11 11:57:58 +0100
commit63c45f4ba533e9749da16298db53e491c25d805b (patch)
treeb3fce35edf1f68221b7487ea729df4e2ef5c3145 /kernel
parentcfa77bc4af2c75c0781ee76cde2dd104c6c8e2b7 (diff)
downloadop-kernel-dev-63c45f4ba533e9749da16298db53e491c25d805b.zip
op-kernel-dev-63c45f4ba533e9749da16298db53e491c25d805b.tar.gz
perf: Disallow user-space stack dumps for function trace events
Recent issues with user space callchains processing within page fault handler tracing showed as Peter said 'there's just too much fail surface'. The user space stack dump is just another source of the this issue. Related list discussions: http://marc.info/?t=139302086500001&r=1&w=2 http://marc.info/?t=139301437300003&r=1&w=2 Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1393775800-13524-3-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/trace/trace_event_perf.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index d5e01c3..c894614 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -42,6 +42,13 @@ static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
*/
if (!p_event->attr.exclude_callchain_user)
return -EINVAL;
+
+ /*
+ * Same reason to disable user stack dump as for user space
+ * callchains above.
+ */
+ if (p_event->attr.sample_type & PERF_SAMPLE_STACK_USER)
+ return -EINVAL;
}
/* No tracing, just counting, so no obvious leak */
OpenPOWER on IntegriCloud