[PATCH 2/3] tracing: Fix parse_synth_field() error handling

[Tom Zanussi]

synth_field_size() returns either the size or an error.  However, the
code assigns the return val to ssize_t which is unsigned, and then
tests whether it's less than 0, which it isn't so discards the error.

Do the test before assignment to field->size.

Signed-off-by: Tom Zanussi <zanu...@kernel.org>
---
 kernel/trace/trace_events_synth.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_events_synth.c 
b/kernel/trace/trace_events_synth.c
index a9cd7793f7ea..6e7282c7b530 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -465,6 +465,7 @@ static struct synth_field *parse_synth_field(int argc, 
const char **argv,
        struct synth_field *field;
        const char *prefix = NULL, *field_type = argv[0], *field_name, *array;
        int len, ret = 0;
+       int size;
 
        if (field_type[0] == ';')
                field_type++;
@@ -520,11 +521,12 @@ static struct synth_field *parse_synth_field(int argc, 
const char **argv,
                        field->type[len - 1] = '\0';
        }
 
-       field->size = synth_field_size(field->type);
-       if (!field->size) {
+       size = synth_field_size(field->type);
+       if (size < 0) {
                ret = -EINVAL;
                goto free;
        }
+       field->size = size;
 
        if (synth_field_is_string(field->type))
                field->is_string = true;
-- 
2.17.1