From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Alexander Shishkin To: Peter Zijlstra Cc: Ingo Molnar , linux-kernel@vger.kernel.org, vince@deater.net, eranian@google.com, Arnaldo Carvalho de Melo , Alexander Shishkin , stable@vger.kernel.org#v4.7 Subject: [PATCH v1 1/3] perf/x86/intel/pt: Fix an off-by-one in address filter configuration Date: Thu, 15 Sep 2016 18:13:50 +0300 Message-Id: <20160915151352.21306-2-alexander.shishkin@linux.intel.com> In-Reply-To: <20160915151352.21306-1-alexander.shishkin@linux.intel.com> References: <20160915151352.21306-1-alexander.shishkin@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: PT address filter configuration requires that a range is specified by its first and last address, but at the moment we're obtaining the end of the range by adding user specified size to its start, which is off by one from what it actually needs to be. Fix this and make sure that zero-sized filters don't pass the filter validation. Cc: stable@vger.kernel.org # v4.7 Reported-by: Adrian Hunter Signed-off-by: Alexander Shishkin --- arch/x86/events/intel/pt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 04bb5fb5a8..5ec0100e3f 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -1081,7 +1081,7 @@ static int pt_event_addr_filters_validate(struct list_head *filters) list_for_each_entry(filter, filters, entry) { /* PT doesn't support single address triggers */ - if (!filter->range) + if (!filter->range || !filter->size) return -EOPNOTSUPP; if (!filter->inode && !kernel_ip(filter->offset)) @@ -1111,7 +1111,7 @@ static void pt_event_addr_filters_sync(struct perf_event *event) } else { /* apply the offset */ msr_a = filter->offset + offs[range]; - msr_b = filter->size + msr_a; + msr_b = filter->size + msr_a - 1; } filters->filter[range].msr_a = msr_a; -- 2.9.3