[PATCH 2/3] perf: Do error out on a kernel filter on an exclude_filter event

From: Alexander Shishkin <alexander.shishkin@linux.intel.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>,
	linux-kernel@vger.kernel.org, vince@deater.net,
	eranian@google.com, Arnaldo Carvalho de Melo <acme@infradead.org>,
	Will Deacon <will.deacon@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Mathieu Poirier <mathieu.poirier@linaro.org>
Subject: [PATCH 2/3] perf: Do error out on a kernel filter on an exclude_filter event
Date: Thu, 26 Jan 2017 11:40:56 +0200	[thread overview]
Message-ID: <20170126094057.13805-3-alexander.shishkin@linux.intel.com> (raw)
In-Reply-To: <20170126094057.13805-1-alexander.shishkin@linux.intel.com>

It is currently possible to configure a kernel address filter for a
event that excludes kernel from its traces (attr.exclude_kernel==1).

While in reality this doesn't make sense, the SET_FILTER ioctl() should
return a error in such case, currently it does not. Furthermore, it
will still silently discard the filter and any potentially valid filters
that came with it.

This patch makes the SET_FILTER ioctl() error out in such cases.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 kernel/events/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index b422b5feee..36770a13ef 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8261,6 +8261,7 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
 		 * attribute.
 		 */
 		if (state == IF_STATE_END) {
+			ret = -EINVAL;
 			if (kernel && event->attr.exclude_kernel)
 				goto fail;
 
-- 
2.11.0
