On 5/28/19 5:48 PM, Steven Rostedt wrote:
> On Tue, 28 May 2019 17:43:38 +0200
> Tomas Bortoli <tomasbort...@gmail.com> wrote:
>
>> In case of errors, predicate_parse() goes to the out_free label
>> to free memory and to return an error code.
>>
>> However, predicate_parse() does not free the predicates of the
>> temporary prog_stack array, thence leaking them.
>
> Thanks, I applied this and I'm running it through my tests. But just an
> FYI, when sending updated patches please add a "v2" to the subject:
>
> [PATCH v2] tracing: Avoid memory leak in predicate_parse()
>
> That way struggling maintainers like myself don't get confused about
> which patch to apply ;-)
>
> Thanks!
>
Yeah, sorry about that, will make sure it doesn't happen again!
Thank you,
Tomas
>
>>
>> Signed-off-by: Tomas Bortoli <tomasbort...@gmail.com>
>> Reported-by: syzbot+6b8e0fb820e570c59...@syzkaller.appspotmail.com
>> ---
>> kernel/trace/trace_events_filter.c | 4 +++-
>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/kernel/trace/trace_events_filter.c
>> b/kernel/trace/trace_events_filter.c
>> index 05a66493a164..ecfa6f0f1c7e 100644
>> --- a/kernel/trace/trace_events_filter.c
>> +++ b/kernel/trace/trace_events_filter.c
>> @@ -427,7 +427,7 @@ predicate_parse(const char *str, int nr_parens, int
>> nr_preds,
>> op_stack = kmalloc_array(nr_parens, sizeof(*op_stack), GFP_KERNEL);
>> if (!op_stack)
>> return ERR_PTR(-ENOMEM);
>> - prog_stack = kmalloc_array(nr_preds, sizeof(*prog_stack), GFP_KERNEL);
>> + prog_stack = kcalloc(nr_preds, sizeof(*prog_stack), GFP_KERNEL);
>> if (!prog_stack) {
>> parse_error(pe, -ENOMEM, 0);
>> goto out_free;
>> @@ -578,6 +578,8 @@ predicate_parse(const char *str, int nr_parens, int
>> nr_preds,
>> out_free:
>> kfree(op_stack);
>> kfree(inverts);
>> + for (i = 0; prog_stack[i].pred; i++)
>> + kfree(prog_stack[i].pred);
>> kfree(prog_stack);
>> return ERR_PTR(ret);
>> }
>
