--- /dev/null
+From 78b562fbfa2cf0a9fcb23c3154756b690f4905c1 Mon Sep 17 00:00:00 2001
+From: Jiri Olsa <jolsa@kernel.org>
+Date: Sun, 15 Apr 2018 11:23:50 +0200
+Subject: perf: Return proper values for user stack errors
+
+From: Jiri Olsa <jolsa@kernel.org>
+
+commit 78b562fbfa2cf0a9fcb23c3154756b690f4905c1 upstream.
+
+Return immediately when we find issue in the user stack checks. The
+error value could get overwritten by following check for
+PERF_SAMPLE_REGS_INTR.
+
+Signed-off-by: Jiri Olsa <jolsa@kernel.org>
+Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
+Cc: Andi Kleen <andi@firstfloor.org>
+Cc: H. Peter Anvin <hpa@zytor.com>
+Cc: Namhyung Kim <namhyung@kernel.org>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Stephane Eranian <eranian@google.com>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Cc: syzkaller-bugs@googlegroups.com
+Cc: x86@kernel.org
+Fixes: 60e2364e60e8 ("perf: Add ability to sample machine state on interrupt")
+Link: http://lkml.kernel.org/r/20180415092352.12403-1-jolsa@kernel.org
+Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ kernel/events/core.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/kernel/events/core.c
++++ b/kernel/events/core.c
+@@ -8133,9 +8133,9 @@ static int perf_copy_attr(struct perf_ev
+ * __u16 sample size limit.
+ */
+ if (attr->sample_stack_user >= USHRT_MAX)
+- ret = -EINVAL;
++ return -EINVAL;
+ else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64)))
+- ret = -EINVAL;
++ return -EINVAL;
+ }
+
+ if (attr->sample_type & PERF_SAMPLE_REGS_INTR)