Re: [PATCH] perf_events: fix bogus copy_to_user() in perf_event_read_group()

[Ingo Molnar <mingo@elte.hu>]

* Stephane Eranian <eranian@google.com> wrote:

> ?? ?? ?? ??When using an event group, the value and id for non leaders events were
> ?? ?? ?? ??wrong due to invalid offset into the outgoing buffer.
> 
> ?? ?? ?? ??Signed-off-by: Stephane Eranian <eranian@google.com>
> 
> ---
> ??perf_event.c | ?? ??2 +-
> ??1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/perf_event.c b/kernel/perf_event.c
> index 0b0d5f7..8306127 100644
> --- a/kernel/perf_event.c
> +++ b/kernel/perf_event.c
> @@ -1826,7 +1826,7 @@ static int perf_event_read_group(struct perf_event *event,
> 
> ?? ?? ?? ?? ?? ?? ?? ??size = n * sizeof(u64);
> 
> - ?? ?? ?? ?? ?? ?? ?? if (copy_to_user(buf + size, values, size)) {
> + ?? ?? ?? ?? ?? ?? ?? if (copy_to_user(buf + ret, values, size)) {
> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ??ret = -EFAULT;
> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ??goto unlock;
> ?? ?? ?? ?? ?? ?? ?? ??}

hm, patch is seriously garbled - mind sending it according to 
Documentation/email-clients.txt?

Thanks,

	Ingo