perf: Return proper values for user stack errors

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: 60e2364e60 ("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>
This commit is contained in:
Jiri Olsa 2018-04-15 11:23:50 +02:00 committed by Arnaldo Carvalho de Melo
parent 038586c343
commit 78b562fbfa

View file

@ -10209,9 +10209,9 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
* __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_max_stack)