From 0ad9f27e997b6a295760e10e71a47dcf18e5dc12 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Wed, 30 Oct 2019 15:47:31 +0200 Subject: [PATCH] perf/aux: Disallow aux_output for kernel events Commit f403171f4e881 ("perf: Allow normal events to output AUX data") added 'aux_output' bit to the attribute structure, which relies on AUX events and grouping, neither of which is supported for the kernel events. This notwithstanding, attempts have been made to use it in the kernel code, suggesting the necessity of an explicit hard -EINVAL. Fix this by rejecting attributes with aux_output set for kernel events. Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Linus Torvalds Cc: Mark Rutland Cc: Namhyung Kim Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Link: https://lkml.kernel.org/r/20191030134731.5437-3-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar --- kernel/events/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index e18d8d34ca77e..7655441065a96 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -11331,6 +11331,13 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, struct perf_event *event; int err; + /* + * Grouping is not supported for kernel events, neither is 'AUX', + * make sure the caller's intentions are adjusted. + */ + if (attr->aux_output) + return ERR_PTR(-EINVAL); + event = perf_event_alloc(attr, cpu, task, NULL, NULL, overflow_handler, context, -1); if (IS_ERR(event)) { -- 2.39.5