On Sun, 4 Oct 2020 17:14:09 -0500
Tom Zanussi <zanu...@kernel.org> wrote:
> From: Steven Rostedt <rost...@goodmis.org>
>
> Change the format for printing synthetic field strings to limit the
> length of the string printed even if it's not correctly terminated.
>
> Description from Steve:
>
> I also added this for a bit of paranoid, and probably should be a
> separate patch, just to make sure if the string isn't nul terminated,
> this will keep it from bleeding pass the end of the string.
Just FYI. In the future, for something like this, you should still have
your own Signed-off-by, as you are sending it (and part of the commit
path). You could also add:
[ Need signed-off-by from Steven ]
Which I would have also added as well.
Thanks!
-- Steve
> ---
> kernel/trace/trace_events_synth.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/trace/trace_events_synth.c
> b/kernel/trace/trace_events_synth.c
> index 24bc6d61aa40..742ce5f62d6d 100644
> --- a/kernel/trace/trace_events_synth.c
> +++ b/kernel/trace/trace_events_synth.c
> @@ -234,7 +234,7 @@ static const char *synth_field_fmt(char *type)
> else if (strcmp(type, "gfp_t") == 0)
> fmt = "%x";
> else if (synth_field_is_string(type))
> - fmt = "%s";
> + fmt = "%.*s";
>
> return fmt;
> }
> @@ -303,11 +303,13 @@ static enum print_line_t print_synth_event(struct
> trace_iterator *iter,
> str_field = (char *)entry + data_offset;
>
> trace_seq_printf(s, print_fmt,
> se->fields[i]->name,
> + STR_VAR_LEN_MAX,
> str_field,
> i == se->n_fields - 1 ? "" : "
> ");
> n_u64++;
> } else {
> trace_seq_printf(s, print_fmt,
> se->fields[i]->name,
> + STR_VAR_LEN_MAX,
> (char *)&entry->fields[n_u64],
> i == se->n_fields - 1 ? "" : "
> ");
> n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
